Delete old, unused code.

# Conflicts:
#	src/main/java/org/nwapw/abacus/plugin/StandardPlugin.java

build.gradle

@@ -1,15 +1,13 @@
-apply plugin: 'java'
-apply plugin: 'application'
+subprojects {
 
-repositories {
-  mavenCentral()
+    apply plugin: 'java'
+
+    repositories {
+      mavenCentral()
+    }
+
+    dependencies {
+        compile "org.jetbrains.kotlin:kotlin-stdlib-jre7:1.1.3"
+    }
 }
 
-dependencies {
-    compile 'com.moandjiezana.toml:toml4j:0.7.1'
-    testCompile 'junit:junit:4.12'
-}
-
-// Define the main class for the application
-mainClassName = 'org.nwapw.abacus.Abacus'
-

core/build.gradle

@@ -0,0 +1,8 @@
+plugins {
+    id 'org.jetbrains.kotlin.jvm' version '1.1.3'
+}
+
+dependencies {
+    compile 'com.moandjiezana.toml:toml4j:0.7.1'
+    testCompile 'junit:junit:4.12'
+}

core/src/main/java/org/nwapw/abacus/Abacus.java

@@ -1,7 +1,6 @@
 package org.nwapw.abacus;
 
 import org.nwapw.abacus.config.Configuration;
-import org.nwapw.abacus.fx.AbacusApplication;
 import org.nwapw.abacus.number.NumberInterface;
 import org.nwapw.abacus.parsing.LexerTokenizer;
 import org.nwapw.abacus.parsing.ShuntingYardParser;
@@ -61,10 +60,6 @@ public class Abacus {
         pluginManager.addListener(lexerTokenizer);
     }
 
-    public static void main(String[] args) {
-        AbacusApplication.launch(AbacusApplication.class, args);
-    }
-
     /**
      * Gets the current tree builder.
      *

core/src/main/java/org/nwapw/abacus/function/DocumentationType.java

@@ -0,0 +1,7 @@
+package org.nwapw.abacus.function;
+
+public enum DocumentationType {
+
+    FUNCTION
+
+}

core/src/main/java/org/nwapw/abacus/number/NaiveNumber.java

@@ -128,5 +128,9 @@ public class NaiveNumber extends NumberInterface {
         return Double.toString(Math.round(value * shiftBy) / shiftBy);
     }
 
+    @Override
+    public NumberInterface getMaxError(){
+        return new NaiveNumber(Math.pow(10, -18));
+    }
 }
 

core/src/main/java/org/nwapw/abacus/number/NumberInterface.java

@@ -182,7 +182,7 @@ public abstract class NumberInterface {
      * Also, checks if the thread has been interrupted, and if so, throws
      * an exception.
      *
-     * @return the least integer bigger or equal to the number, if int can hold the value.
+     * @return the least integer bigger or equal to the number.
      */
     public final NumberInterface ceiling(){
         checkInterrupted();
@@ -192,7 +192,7 @@ public abstract class NumberInterface {
     /**
      * Return the greatest integer less than or equal to the number.
      *
-     * @return the greatest integer smaller or equal the number, if int can hold the value.
+     * @return the greatest integer smaller or equal the number.
      */
     protected abstract NumberInterface floorInternal();
 
@@ -201,7 +201,7 @@ public abstract class NumberInterface {
      * Also, checks if the thread has been interrupted, and if so, throws
      * an exception.
      *
-     * @return the greatest int smaller or equal to the number, if int can hold the value.
+     * @return the greatest int smaller than or equal to the number.
      */
     public final NumberInterface floor(){
         checkInterrupted();
@@ -216,7 +216,7 @@ public abstract class NumberInterface {
     protected abstract NumberInterface fractionalPartInternal();
 
     /**
-     * Returns the fractional part of the number.
+     * Returns the fractional part of the number, specifically x - floor(x).
      * Also, checks if the thread has been interrupted,
      * and if so, throws an exception.
      * @return the fractional part of the number.
@@ -240,6 +240,7 @@ public abstract class NumberInterface {
      * @param toClass the class to promote to.
      * @return the resulting new instance.
      */
+    @Deprecated
     protected abstract NumberInterface promoteToInternal(Class<? extends NumberInterface> toClass);
 
     /**
@@ -250,9 +251,17 @@ public abstract class NumberInterface {
      * @param toClass the class to promote to.
      * @return the resulting new instance.
      */
+    @Deprecated
     public final NumberInterface promoteTo(Class<? extends NumberInterface> toClass) {
         checkInterrupted();
         return promoteToInternal(toClass);
     }
 
+    /**
+     * Returns the smallest error this instance can tolerate depending
+     * on its precision and value.
+     * @return the smallest error that should be permitted in calculations.
+     */
+    public abstract NumberInterface getMaxError();
+
 }

core/src/main/java/org/nwapw/abacus/number/PreciseNumber.java

@@ -1,7 +1,7 @@
 package org.nwapw.abacus.number;
 
 import java.math.BigDecimal;
-import java.math.RoundingMode;
+import java.math.MathContext;
 
 /**
  * A number that uses a BigDecimal to store its value,
@@ -22,6 +22,21 @@ public class PreciseNumber extends NumberInterface {
      */
     public static final PreciseNumber TEN = new PreciseNumber(BigDecimal.TEN);
 
+    /**
+     * The number of extra significant figures kept in calculations before rounding for output.
+     */
+    private static int numExtraInternalSigFigs = 15;
+
+    /**
+     * MathContext that is used when rounding a number prior to output.
+     */
+    private static MathContext outputContext = new MathContext(50);
+
+    /**
+     * MathContext that is actually used in calculations.
+     */
+    private static MathContext internalContext = new MathContext(outputContext.getPrecision()+numExtraInternalSigFigs);
+
     /**
      * The value of the PreciseNumber.
      */
@@ -48,7 +63,7 @@ public class PreciseNumber extends NumberInterface {
 
     @Override
     public int getMaxPrecision() {
-        return 65;
+        return internalContext.getPrecision();
     }
 
     @Override
@@ -58,7 +73,7 @@ public class PreciseNumber extends NumberInterface {
 
     @Override
     public NumberInterface divideInternal(NumberInterface divisor) {
-        return new PreciseNumber(value.divide(((PreciseNumber) divisor).value, this.getMaxPrecision(), RoundingMode.HALF_UP));
+        return new PreciseNumber(value.divide(((PreciseNumber) divisor).value, internalContext));
     }
 
     @Override
@@ -113,19 +128,18 @@ public class PreciseNumber extends NumberInterface {
         String str = value.toPlainString();
         int decimalIndex = str.indexOf('.');
         if (decimalIndex != -1) {
-            return new PreciseNumber(str.substring(0, decimalIndex));
+            NumberInterface floor = new PreciseNumber(str.substring(0, decimalIndex));
+            if(signum() == -1){
+                floor = floor.subtract(ONE);
+            }
+            return floor;
         }
         return this;
     }
 
     @Override
     public NumberInterface fractionalPartInternal() {
-        String str = value.toPlainString();
-        int decimalIndex = str.indexOf('.');
-        if (decimalIndex != -1) {
-            return new PreciseNumber(str.substring(decimalIndex + 1));
-        }
-        return ZERO;
+        return this.subtractInternal(floorInternal());
     }
 
     @Override
@@ -148,7 +162,11 @@ public class PreciseNumber extends NumberInterface {
 
     @Override
     public String toString() {
-        BigDecimal rounded = value.setScale(getMaxPrecision() - 15, RoundingMode.HALF_UP);
-        return rounded.stripTrailingZeros().toPlainString();
+        return value.round(outputContext).toString();
+    }
+
+    @Override
+    public NumberInterface getMaxError(){
+        return new PreciseNumber(value.ulp()).multiplyInternal(TEN.intPowInternal(value.precision()-internalContext.getPrecision()));
     }
 }

core/src/main/java/org/nwapw/abacus/plugin/NumberImplementation.java

@@ -14,7 +14,7 @@ public abstract class NumberImplementation {
     /**
      * The list of paths through which this implementation can be promoted.
      */
-    protected Map<Class<? extends NumberInterface>, Function<NumberInterface, NumberInterface>> promotionPaths;
+    private Map<Class<? extends NumberInterface>, Function<NumberInterface, NumberInterface>> promotionPaths;
     /**
      * The implementation class for this implementation.
      */

core/src/main/java/org/nwapw/abacus/plugin/Plugin.java

@@ -1,5 +1,7 @@
 package org.nwapw.abacus.plugin;
 
+import org.nwapw.abacus.function.Documentation;
+import org.nwapw.abacus.function.DocumentationType;
 import org.nwapw.abacus.function.Function;
 import org.nwapw.abacus.function.Operator;
 import org.nwapw.abacus.number.NumberInterface;
@@ -94,6 +96,15 @@ public abstract class Plugin {
         manager.registerNumberImplementation(name, implementation);
     }
 
+    /**
+     * To be used in load(). Registers a documentation instance
+     * used to explain some element of the plugin to the user.
+     * @param documentation the documentation instance.
+     */
+    protected final void registerDocumentation(Documentation documentation){
+        manager.registerDocumentation(documentation);
+    }
+
     /**
      * Searches the PluginManager for the given function name.
      * This can be used by the plugins internally in order to call functions
@@ -130,6 +141,17 @@ public abstract class Plugin {
         return manager.numberImplementationFor(name);
     }
 
+    /**
+     * Searches the PluginManager for the given documentation name and type.
+     *
+     * @param name the name for which to search.
+     * @param type the type of documentation to search for.
+     * @return the found documentation, or null if none was found.
+     */
+    protected final Documentation documentationFor(String name, DocumentationType type){
+        return manager.documentationFor(name, type);
+    }
+
     /**
      * Searches the plugin manager for a Pi value for the given number implementation.
      * This is done so that number implementations with various degrees of precision

core/src/main/java/org/nwapw/abacus/plugin/PluginManager.java

@@ -1,6 +1,8 @@
 package org.nwapw.abacus.plugin;
 
 import org.nwapw.abacus.Abacus;
+import org.nwapw.abacus.function.Documentation;
+import org.nwapw.abacus.function.DocumentationType;
 import org.nwapw.abacus.function.Function;
 import org.nwapw.abacus.function.Operator;
 import org.nwapw.abacus.number.NumberInterface;
@@ -34,6 +36,10 @@ public class PluginManager {
      * The map of number implementations registered by the plugins.
      */
     private Map<String, NumberImplementation> registeredNumberImplementations;
+    /**
+     * The map of documentation for functions registered by the plugins.
+     */
+    private Set<Documentation> registeredDocumentation;
     /**
      * The list of number implementations that have been
      * found by their implementation class.
@@ -65,6 +71,7 @@ public class PluginManager {
         registeredFunctions = new HashMap<>();
         registeredOperators = new HashMap<>();
         registeredNumberImplementations = new HashMap<>();
+        registeredDocumentation = new HashSet<>();
         cachedInterfaceImplementations = new HashMap<>();
         cachedPi = new HashMap<>();
         listeners = new HashSet<>();
@@ -97,6 +104,15 @@ public class PluginManager {
         registeredNumberImplementations.put(name, implementation);
     }
 
+    /**
+     * Registers the given documentation with the plugin manager,
+     * making it accessible to the plugin manager etc.
+     * @param documentation the documentation to register.
+     */
+    public void registerDocumentation(Documentation documentation){
+        registeredDocumentation.add(documentation);
+    }
+
     /**
      * Gets the function registered under the given name.
      * @param name the name of the function.
@@ -124,6 +140,27 @@ public class PluginManager {
         return registeredNumberImplementations.get(name);
     }
 
+    /**
+     * Gets the documentation for the given entity of the given type.
+     * @param name the name of the entity to search for.
+     * @param type the type that this entity is, to filter out similarly named documentation.
+     * @return the documentation object.
+     */
+    public Documentation documentationFor(String name, DocumentationType type){
+        Documentation toReturn = null;
+        for(Documentation entry : registeredDocumentation){
+            if(entry.getCodeName().equals(name) && entry.getType() == type) {
+                toReturn = entry;
+                break;
+            }
+        }
+        if(toReturn == null){
+            toReturn = new Documentation(name, "", "", "", type);
+            registerDocumentation(toReturn);
+        }
+        return toReturn;
+    }
+
     /**
      * Gets the number implementation for the given implementation class.
      *
@@ -187,6 +224,24 @@ public class PluginManager {
         }
     }
 
+    /**
+     * Removes the plugin with the given class from the manager.
+     * @param toRemove the plugin to remove.
+     */
+    public void removeClass(Class<? extends Plugin> toRemove){
+        if(!loadedPluginClasses.contains(toRemove)) return;
+        plugins.removeIf(plugin -> plugin.getClass() == toRemove);
+        loadedPluginClasses.remove(toRemove);
+    }
+
+    /**
+     * Removes all plugins from this plugin manager.
+     */
+    public void removeAll(){
+        loadedPluginClasses.clear();
+        plugins.clear();
+    }
+
     /**
      * Loads all the plugins in the PluginManager.
      */
@@ -212,6 +267,7 @@ public class PluginManager {
         registeredFunctions.clear();
         registeredOperators.clear();
         registeredNumberImplementations.clear();
+        registeredDocumentation.clear();
         cachedInterfaceImplementations.clear();
         cachedPi.clear();
         listeners.forEach(e -> e.onUnload(this));

core/src/main/java/org/nwapw/abacus/plugin/StandardPlugin.java

@@ -1,15 +1,19 @@
 package org.nwapw.abacus.plugin;
 
-import org.nwapw.abacus.function.Function;
-import org.nwapw.abacus.function.Operator;
-import org.nwapw.abacus.function.OperatorAssociativity;
-import org.nwapw.abacus.function.OperatorType;
+import org.nwapw.abacus.function.*;
+import org.nwapw.abacus.lexing.pattern.Match;
 import org.nwapw.abacus.number.NaiveNumber;
 import org.nwapw.abacus.number.NumberInterface;
 import org.nwapw.abacus.number.PreciseNumber;
+import org.nwapw.abacus.parsing.Parser;
+import org.nwapw.abacus.parsing.ShuntingYardParser;
+import org.nwapw.abacus.tree.TokenType;
+import org.nwapw.abacus.tree.TreeNode;
 
 import java.util.ArrayList;
+import java.util.Date;
 import java.util.HashMap;
+import java.util.List;
 import java.util.function.BiFunction;
 
 /**
@@ -94,7 +98,7 @@ public class StandardPlugin extends Plugin {
     public static final Operator OP_DIVIDE = new Operator(OperatorAssociativity.LEFT, OperatorType.BINARY_INFIX, 1, new Function() {
         @Override
         protected boolean matchesParams(NumberInterface[] params) {
-            return params.length == 2 && params[1].compareTo(NaiveNumber.ZERO.promoteTo(params[1].getClass())) != 0;
+            return params.length == 2 && params[1].compareTo(fromInt(params[0].getClass(), 0)) != 0;
         }
 
         @Override
@@ -110,7 +114,7 @@ public class StandardPlugin extends Plugin {
         @Override
         protected boolean matchesParams(NumberInterface[] params) {
             return params.length == 1
-                    && params[0].fractionalPart().compareTo(NaiveNumber.ZERO.promoteTo(params[0].getClass())) == 0
+                    && params[0].fractionalPart().compareTo(fromInt(params[0].getClass(), 0)) == 0
                     && params[0].signum() >= 0;
         }
 
@@ -119,10 +123,11 @@ public class StandardPlugin extends Plugin {
             if (params[0].signum() == 0) {
                 return fromInt(params[0].getClass(), 1);
             }
+            NumberInterface one = fromInt(params[0].getClass(), 1);
             NumberInterface factorial = params[0];
             NumberInterface multiplier = params[0];
             //It is necessary to later prevent calls of factorial on anything but non-negative integers.
-            while ((multiplier = multiplier.subtract(NaiveNumber.ONE.promoteTo(multiplier.getClass()))).signum() == 1) {
+            while ((multiplier = multiplier.subtract(one)).signum() == 1) {
                 factorial = factorial.multiply(multiplier);
             }
             return factorial;
@@ -133,6 +138,51 @@ public class StandardPlugin extends Plugin {
                 }*/
         }
     });
+    /**
+     * The permutation operator.
+     */
+    public static final Operator OP_NPR = new Operator(OperatorAssociativity.RIGHT, OperatorType.BINARY_INFIX, 0, new Function() {
+        @Override
+        protected boolean matchesParams(NumberInterface[] params) {
+            return params.length == 2 && params[0].fractionalPart().signum() == 0
+                    && params[1].fractionalPart().signum() == 0;
+        }
+
+        @Override
+        protected NumberInterface applyInternal(NumberInterface[] params) {
+            if(params[0].compareTo(params[1]) < 0 ||
+                    params[0].signum() < 0 ||
+                    (params[0].signum() == 0 && params[1].signum() != 0)) return fromInt(params[0].getClass(), 0);
+            NumberInterface total = fromInt(params[0].getClass(), 1);
+            NumberInterface multiplyBy = params[0];
+            NumberInterface remainingMultiplications = params[1];
+            NumberInterface halfway = params[0].divide(fromInt(params[0].getClass(), 2));
+            if(remainingMultiplications.compareTo(halfway) > 0){
+                remainingMultiplications = params[0].subtract(remainingMultiplications);
+            }
+            while(remainingMultiplications.signum() > 0){
+                total = total.multiply(multiplyBy);
+                remainingMultiplications = remainingMultiplications.subtract(fromInt(params[0].getClass(), 1));
+                multiplyBy = multiplyBy.subtract(fromInt(params[0].getClass(), 1));
+            }
+            return total;
+        }
+    });
+    /**
+     * The combination operator.
+     */
+    public static final Operator OP_NCR = new Operator(OperatorAssociativity.RIGHT, OperatorType.BINARY_INFIX, 0, new Function() {
+        @Override
+        protected boolean matchesParams(NumberInterface[] params) {
+            return params.length == 2 && params[0].fractionalPart().signum() == 0
+                    && params[1].fractionalPart().signum() == 0;
+        }
+
+        @Override
+        protected NumberInterface applyInternal(NumberInterface[] params) {
+            return OP_NPR.getFunction().apply(params).divide(OP_FACTORIAL.getFunction().apply(params[1]));
+        }
+    });
     /**
      * The absolute value function, abs(-3) = 3
      */
@@ -144,7 +194,7 @@ public class StandardPlugin extends Plugin {
 
         @Override
         protected NumberInterface applyInternal(NumberInterface[] params) {
-            return params[0].multiply((new NaiveNumber(params[0].signum())).promoteTo(params[0].getClass()));
+            return params[0].multiply(fromInt(params[0].getClass(), params[0].signum()));
         }
     };
     /**
@@ -153,31 +203,32 @@ public class StandardPlugin extends Plugin {
     public static final Function FUNCTION_LN = new Function() {
         @Override
         protected boolean matchesParams(NumberInterface[] params) {
-            return params.length == 1 && params[0].compareTo(NaiveNumber.ZERO.promoteTo(params[0].getClass())) > 0;
+            return params.length == 1 && params[0].compareTo(fromInt(params[0].getClass(), 0)) > 0;
         }
 
         @Override
         protected NumberInterface applyInternal(NumberInterface[] params) {
             NumberInterface param = params[0];
+            NumberInterface one = fromInt(param.getClass(), 1);
             int powersOf2 = 0;
-            while (FUNCTION_ABS.apply(param.subtract(NaiveNumber.ONE.promoteTo(param.getClass()))).compareTo(new NaiveNumber(0.1).promoteTo(param.getClass())) >= 0) {
-                if (param.subtract(NaiveNumber.ONE.promoteTo(param.getClass())).signum() == 1) {
+            while (FUNCTION_ABS.apply(param.subtract(one)).compareTo(new NaiveNumber(0.1).promoteTo(param.getClass())) >= 0) {
+                if (param.subtract(one).signum() == 1) {
                     param = param.divide(fromInt(param.getClass(), 2));
                     powersOf2++;
-                    if (param.subtract(NaiveNumber.ONE.promoteTo(param.getClass())).signum() != 1) {
+                    if (param.subtract(one).signum() != 1) {
                         break;
                         //No infinite loop for you.
                     }
                 } else {
                     param = param.multiply(fromInt(param.getClass(), 2));
                     powersOf2--;
-                    if (param.subtract(NaiveNumber.ONE.promoteTo(param.getClass())).signum() != -1) {
+                    if (param.subtract(one).signum() != -1) {
                         break;
                         //No infinite loop for you.
                     }
                 }
             }
-            return getLog2(param).multiply((new NaiveNumber(powersOf2)).promoteTo(param.getClass())).add(getLogPartialSum(param));
+            return getLog2(param).multiply(fromInt(param.getClass(), powersOf2)).add(getLogPartialSum(param));
         }
 
         /**
@@ -188,14 +239,14 @@ public class StandardPlugin extends Plugin {
          */
         private NumberInterface getLogPartialSum(NumberInterface x) {
 
-            NumberInterface maxError = getMaxError(x);
-            x = x.subtract(NaiveNumber.ONE.promoteTo(x.getClass())); //Terms used are for log(x+1).
+            NumberInterface maxError = x.getMaxError();
+            x = x.subtract(fromInt(x.getClass(), 1)); //Terms used are for log(x+1).
             NumberInterface currentNumerator = x, currentTerm = x, sum = x;
             int n = 1;
             while (FUNCTION_ABS.apply(currentTerm).compareTo(maxError) > 0) {
                 n++;
                 currentNumerator = currentNumerator.multiply(x).negate();
-                currentTerm = currentNumerator.divide(new NaiveNumber(n).promoteTo(x.getClass()));
+                currentTerm = currentNumerator.divide(fromInt(x.getClass(), n));
                 sum = sum.add(currentTerm);
             }
             return sum;
@@ -207,19 +258,20 @@ public class StandardPlugin extends Plugin {
          * @return the value of log(2) with the appropriate precision.
          */
         private NumberInterface getLog2(NumberInterface number) {
-            NumberInterface maxError = getMaxError(number);
+            NumberInterface maxError = number.getMaxError();
             //NumberInterface errorBound = fromInt(number.getClass(), 1);
             //We'll use the series \sigma_{n >= 1) ((1/3^n + 1/4^n) * 1/n)
             //In the following, a=1/3^n, b=1/4^n, c = 1/n.
             //a is also an error bound.
             NumberInterface a = fromInt(number.getClass(), 1), b = a, c = a;
-            NumberInterface sum = NaiveNumber.ZERO.promoteTo(number.getClass());
+            NumberInterface sum = fromInt(number.getClass(), 0);
+            NumberInterface one = fromInt(number.getClass(), 1);
             int n = 0;
             while (a.compareTo(maxError) >= 1) {
                 n++;
                 a = a.divide(fromInt(number.getClass(), 3));
                 b = b.divide(fromInt(number.getClass(), 4));
-                c = NaiveNumber.ONE.promoteTo(number.getClass()).divide((new NaiveNumber(n)).promoteTo(number.getClass()));
+                c = one.divide(fromInt(number.getClass(), n));
                 sum = sum.add(a.add(b).multiply(c));
             }
             return sum;
@@ -239,6 +291,20 @@ public class StandardPlugin extends Plugin {
             return OP_CARET.getFunction().apply(params[0], ((new NaiveNumber(0.5)).promoteTo(params[0].getClass())));
         }
     };
+    /**
+     * Gets a random number smaller or equal to the given number's integer value.
+     */
+    public static final Function FUNCTION_RAND_INT = new Function() {
+        @Override
+        protected boolean matchesParams(NumberInterface[] params) {
+            return params.length == 1;
+        }
+
+        @Override
+        protected NumberInterface applyInternal(NumberInterface[] params) {
+            return fromInt(params[0].getClass(), (int) Math.round(Math.random() * params[0].floor().intValue()));
+        }
+    };
     /**
      * The implementation for double-based naive numbers.
      */
@@ -278,10 +344,10 @@ public class StandardPlugin extends Plugin {
                     .negate();
             for (int i = 0; i < termsNeeded; i++) {
                 M = M
-                        .multiply(new NaiveNumber(12 * i + 2).promoteTo(PreciseNumber.class))
-                        .multiply(new NaiveNumber(12 * i + 6).promoteTo(PreciseNumber.class))
-                        .multiply(new NaiveNumber(12 * i + 10).promoteTo(PreciseNumber.class))
-                        .divide(new NaiveNumber(Math.pow(i + 1, 3)).promoteTo(PreciseNumber.class));
+                        .multiply(new PreciseNumber((12 * i + 2) + ""))
+                        .multiply(new PreciseNumber((12 * i + 6) + ""))
+                        .multiply(new PreciseNumber((12 * i + 10) + ""))
+                        .divide(new PreciseNumber(Math.pow(i + 1, 3) + ""));
                 L = L.add(lSummand);
                 X = X.multiply(xMultiplier);
                 sum = sum.add(M.multiply(L).divide(X));
@@ -301,20 +367,15 @@ public class StandardPlugin extends Plugin {
 
         @Override
         protected NumberInterface applyInternal(NumberInterface[] params) {
-            NumberInterface maxError = getMaxError(params[0]);
+            NumberInterface maxError = params[0].getMaxError();
             int n = 0;
-            if (params[0].signum() <= 0) {
-                NumberInterface currentTerm = NaiveNumber.ONE.promoteTo(params[0].getClass()), sum = currentTerm;
-                while (FUNCTION_ABS.apply(currentTerm).compareTo(maxError) > 0) {
-                    n++;
-                    currentTerm = currentTerm.multiply(params[0]).divide((new NaiveNumber(n)).promoteTo(params[0].getClass()));
-                    sum = sum.add(currentTerm);
-                }
-                return sum;
+            if (params[0].signum() < 0) {
+                NumberInterface[] negatedParams = {params[0].negate()};
+               return fromInt(params[0].getClass(), 1).divide(applyInternal(negatedParams));
             } else {
                 //We need n such that x^(n+1) * 3^ceil(x) <= maxError * (n+1)!.
                 //right and left refer to lhs and rhs in the above inequality.
-                NumberInterface sum = NaiveNumber.ONE.promoteTo(params[0].getClass());
+                NumberInterface sum = fromInt(params[0].getClass(), 1);
                 NumberInterface nextNumerator = params[0];
                 NumberInterface left = params[0].multiply(fromInt(params[0].getClass(), 3).intPow(params[0].ceiling().intValue())), right = maxError;
                 do {
@@ -322,7 +383,7 @@ public class StandardPlugin extends Plugin {
                     n++;
                     nextNumerator = nextNumerator.multiply(params[0]);
                     left = left.multiply(params[0]);
-                    NumberInterface nextN = (new NaiveNumber(n + 1)).promoteTo(params[0].getClass());
+                    NumberInterface nextN = fromInt(params[0].getClass(), n + 1);
                     right = right.multiply(nextN);
                     //System.out.println(left + ", " + right);
                 }
@@ -338,17 +399,27 @@ public class StandardPlugin extends Plugin {
     public static final Operator OP_CARET = new Operator(OperatorAssociativity.RIGHT, OperatorType.BINARY_INFIX, 2, new Function() {
         @Override
         protected boolean matchesParams(NumberInterface[] params) {
+            NumberInterface zero = fromInt(params[0].getClass(), 0);
             return params.length == 2
-                    && !(params[0].compareTo(NaiveNumber.ZERO.promoteTo(params[0].getClass())) == 0
-                    && params[1].compareTo(NaiveNumber.ZERO.promoteTo(params[1].getClass())) == 0);
+                    && !(params[0].compareTo(zero) == 0
+                    && params[1].compareTo(zero) == 0)
+                    && !(params[0].signum() == -1 && params[1].fractionalPart().compareTo(zero) != 0);
         }
 
         @Override
         protected NumberInterface applyInternal(NumberInterface[] params) {
-            if (params[0].compareTo(NaiveNumber.ZERO.promoteTo(params[0].getClass())) == 0)
-                return NaiveNumber.ZERO.promoteTo(params[0].getClass());
-            else if (params[1].compareTo(NaiveNumber.ZERO.promoteTo(params[0].getClass())) == 0)
-                return NaiveNumber.ONE.promoteTo(params[1].getClass());
+            NumberInterface zero = fromInt(params[0].getClass(), 0);
+            if (params[0].compareTo(zero) == 0)
+                return zero;
+            else if (params[1].compareTo(zero) == 0)
+                return fromInt(params[0].getClass(), 1);
+            //Detect integer bases:
+            if(params[0].fractionalPart().compareTo(fromInt(params[0].getClass(), 0)) == 0
+                    && FUNCTION_ABS.apply(params[1]).compareTo(fromInt(params[0].getClass(), Integer.MAX_VALUE)) < 0
+                    && FUNCTION_ABS.apply(params[1]).compareTo(fromInt(params[1].getClass(), 1)) >= 0){
+                NumberInterface[] newParams = {params[0], params[1].fractionalPart()};
+                return params[0].intPow(params[1].floor().intValue()).multiply(applyInternal(newParams));
+            }
             return FUNCTION_EXP.apply(FUNCTION_LN.apply(FUNCTION_ABS.apply(params[0])).multiply(params[1]));
         }
     });
@@ -416,7 +487,7 @@ public class StandardPlugin extends Plugin {
 
         @Override
         protected NumberInterface applyInternal(NumberInterface[] params) {
-            return NaiveNumber.ONE.promoteTo(params[0].getClass()).divide(functionCos.apply(params[0]));
+            return fromInt(params[0].getClass(), 1).divide(functionCos.apply(params[0]));
         }
     };
     /**
@@ -430,7 +501,7 @@ public class StandardPlugin extends Plugin {
 
         @Override
         protected NumberInterface applyInternal(NumberInterface[] params) {
-            return NaiveNumber.ONE.promoteTo(params[0].getClass()).divide(functionSin.apply(params[0]));
+            return fromInt(params[0].getClass(), 1).divide(functionSin.apply(params[0]));
         }
     };
     /**
@@ -448,6 +519,144 @@ public class StandardPlugin extends Plugin {
         }
     };
 
+    /**
+     * The arcsine function (return type in radians).
+     */
+    public final Function functionArcsin = new Function() {
+        @Override
+        protected boolean matchesParams(NumberInterface[] params) {
+            return params.length == 1
+                    && FUNCTION_ABS.apply(params[0]).compareTo(fromInt(params[0].getClass(), 1)) <= 0;
+        }
+
+        @Override
+        protected NumberInterface applyInternal(NumberInterface[] params) {
+            if(FUNCTION_ABS.apply(params[0]).compareTo(new NaiveNumber(0.8).promoteTo(params[0].getClass())) >= 0){
+                NumberInterface[] newParams = {FUNCTION_SQRT.apply(fromInt(params[0].getClass(), 1).subtract(params[0].multiply(params[0])))};
+                return piFor(params[0].getClass()).divide(fromInt(params[0].getClass(), 2))
+                        .subtract(applyInternal(newParams)).multiply(fromInt(params[0].getClass(), params[0].signum()));
+            }
+            NumberInterface currentTerm = params[0], sum = currentTerm,
+                    multiplier = currentTerm.multiply(currentTerm), summandBound = sum.getMaxError().multiply(fromInt(sum.getClass(), 1).subtract(multiplier)),
+                    power = currentTerm, coefficient = fromInt(params[0].getClass(), 1);
+            int exponent = 1;
+            while(FUNCTION_ABS.apply(currentTerm).compareTo(summandBound) > 0){
+                exponent += 2;
+                power = power.multiply(multiplier);
+                coefficient = coefficient.multiply(fromInt(params[0].getClass(), exponent-2))
+                        .divide(fromInt(params[0].getClass(), exponent - 1));
+                currentTerm = power.multiply(coefficient).divide(fromInt(power.getClass(), exponent));
+                sum = sum.add(currentTerm);
+            }
+            return sum;
+        }
+    };
+
+    /**
+     * The arccosine function.
+     */
+    public final Function functionArccos = new Function() {
+        @Override
+        protected boolean matchesParams(NumberInterface[] params) {
+            return params.length == 1 && FUNCTION_ABS.apply(params[0]).compareTo(fromInt(params[0].getClass(), 1)) <= 0;
+        }
+
+        @Override
+        protected NumberInterface applyInternal(NumberInterface[] params) {
+            return piFor(params[0].getClass()).divide(fromInt(params[0].getClass(), 2))
+                    .subtract(functionArcsin.apply(params));
+        }
+    };
+
+    /**
+     * The arccosecant function.
+     */
+    public final Function functionArccsc = new Function() {
+        @Override
+        protected boolean matchesParams(NumberInterface[] params) {
+            return params.length == 1 && FUNCTION_ABS.apply(params[0]).compareTo(fromInt(params[0].getClass(), 1)) >= 0;
+        }
+
+        @Override
+        protected NumberInterface applyInternal(NumberInterface[] params) {
+            NumberInterface[] reciprocalParamArr = {fromInt(params[0].getClass(), 1).divide(params[0])};
+            return functionArcsin.apply(reciprocalParamArr);
+        }
+    };
+
+    /**
+     * The arcsecant function.
+     */
+    public final Function functionArcsec = new Function() {
+        @Override
+        protected boolean matchesParams(NumberInterface[] params) {
+            return params.length == 1 && FUNCTION_ABS.apply(params[0]).compareTo(fromInt(params[0].getClass(), 1)) >= 0;
+        }
+
+        @Override
+        protected NumberInterface applyInternal(NumberInterface[] params) {
+            NumberInterface[] reciprocalParamArr = {fromInt(params[0].getClass(), 1).divide(params[0])};
+            return functionArccos.apply(reciprocalParamArr);
+        }
+    };
+
+    /**
+     * The arctangent function.
+     */
+    public final Function functionArctan = new Function() {
+        @Override
+        protected boolean matchesParams(NumberInterface[] params) {
+            return params.length == 1;
+        }
+
+        @Override
+        protected NumberInterface applyInternal(NumberInterface[] params) {
+            if(params[0].signum() == -1){
+                NumberInterface[] negatedParams = {params[0].negate()};
+                return applyInternal(negatedParams).negate();
+            }
+            if(params[0].compareTo(fromInt(params[0].getClass(), 1)) > 0){
+                NumberInterface[] reciprocalParams = {fromInt(params[0].getClass(), 1).divide(params[0])};
+                return piFor(params[0].getClass()).divide(fromInt(params[0].getClass(), 2))
+                        .subtract(applyInternal(reciprocalParams));
+            }
+            if(params[0].compareTo(fromInt(params[0].getClass(), 1)) == 0){
+                return piFor(params[0].getClass()).divide(fromInt(params[0].getClass(), 4));
+            }
+            if(params[0].compareTo(new NaiveNumber(0.9).promoteTo(params[0].getClass())) >= 0){
+                NumberInterface[] newParams = {params[0].multiply(fromInt(params[0].getClass(),2 ))
+                .divide(fromInt(params[0].getClass(), 1).subtract(params[0].multiply(params[0])))};
+                return applyInternal(newParams).divide(fromInt(params[0].getClass(), 2));
+            }
+            NumberInterface currentPower = params[0], currentTerm = currentPower, sum = currentTerm,
+                    maxError = params[0].getMaxError(), multiplier = currentPower.multiply(currentPower).negate();
+            int n = 1;
+            while(FUNCTION_ABS.apply(currentTerm).compareTo(maxError) > 0){
+                n += 2;
+                currentPower = currentPower.multiply(multiplier);
+                currentTerm = currentPower.divide(fromInt(currentPower.getClass(), n));
+                sum = sum.add(currentTerm);
+            }
+            return sum;
+        }
+    };
+
+    /**
+     * The arccotangent function. Range: (0, pi).
+     */
+    public final Function functionArccot = new Function() {
+        @Override
+        protected boolean matchesParams(NumberInterface[] params) {
+            return params.length == 1;
+        }
+
+        @Override
+        protected NumberInterface applyInternal(NumberInterface[] params) {
+            return piFor(params[0].getClass()).divide(fromInt(params[0].getClass(), 2))
+                    .subtract(functionArctan.apply(params));
+        }
+    };
+
     public StandardPlugin(PluginManager manager) {
         super(manager);
     }
@@ -461,23 +670,13 @@ public class StandardPlugin extends Plugin {
      * @return the value of the partial sum that has the same class as x.
      */
     private static NumberInterface sumSeries(NumberInterface x, BiFunction<Integer, NumberInterface, NumberInterface> nthTermFunction, int n) {
-        NumberInterface sum = NaiveNumber.ZERO.promoteTo(x.getClass());
+        NumberInterface sum = fromInt(x.getClass(), 0);
         for (int i = 0; i <= n; i++) {
             sum = sum.add(nthTermFunction.apply(i, x));
         }
         return sum;
     }
 
-    /**
-     * Returns the maximum error based on the precision of the class of number.
-     *
-     * @param number Any instance of the NumberInterface in question (should return an appropriate precision).
-     * @return the maximum error.
-     */
-    private static NumberInterface getMaxError(NumberInterface number) {
-        return fromInt(number.getClass(), 10).intPow(-number.getMaxPrecision());
-    }
-
     /**
      * A factorial function that uses memoization for each number class; it efficiently
      * computes factorials of non-negative integers.
@@ -489,13 +688,13 @@ public class StandardPlugin extends Plugin {
     public static NumberInterface factorial(Class<? extends NumberInterface> numberClass, int n) {
         if (!FACTORIAL_LISTS.containsKey(numberClass)) {
             FACTORIAL_LISTS.put(numberClass, new ArrayList<>());
-            FACTORIAL_LISTS.get(numberClass).add(NaiveNumber.ONE.promoteTo(numberClass));
-            FACTORIAL_LISTS.get(numberClass).add(NaiveNumber.ONE.promoteTo(numberClass));
+            FACTORIAL_LISTS.get(numberClass).add(fromInt(numberClass, 1));
+            FACTORIAL_LISTS.get(numberClass).add(fromInt(numberClass, 1));
         }
         ArrayList<NumberInterface> list = FACTORIAL_LISTS.get(numberClass);
         if (n >= list.size()) {
             while (list.size() < n + 16) {
-                list.add(list.get(list.size() - 1).multiply(new NaiveNumber(list.size()).promoteTo(numberClass)));
+                list.add(list.get(list.size() - 1).multiply(fromInt(numberClass, list.size())));
             }
         }
         return list.get(n);
@@ -509,7 +708,7 @@ public class StandardPlugin extends Plugin {
      */
     private static NumberInterface sinTaylor(NumberInterface x) {
         NumberInterface power = x, multiplier = x.multiply(x).negate(), currentTerm = x, sum = x;
-        NumberInterface maxError = getMaxError(x);
+        NumberInterface maxError = x.getMaxError();
         int n = 1;
         do {
             n += 2;
@@ -527,7 +726,7 @@ public class StandardPlugin extends Plugin {
      * @return theta in [0, 2pi) that differs from phi by a multiple of 2pi.
      */
     private static NumberInterface getSmallAngle(NumberInterface phi, NumberInterface pi) {
-        NumberInterface twoPi = pi.multiply(new NaiveNumber("2").promoteTo(phi.getClass()));
+        NumberInterface twoPi = pi.multiply(fromInt(pi.getClass(), 2));
         NumberInterface theta = FUNCTION_ABS.apply(phi).subtract(twoPi
                 .multiply(FUNCTION_ABS.apply(phi).divide(twoPi).floor())); //Now theta is in [0, 2pi).
         if (phi.signum() < 0) {
@@ -565,16 +764,77 @@ public class StandardPlugin extends Plugin {
         registerOperator("^", OP_CARET);
         registerOperator("!", OP_FACTORIAL);
 
+        registerOperator("nPr", OP_NPR);
+        registerOperator("nCr", OP_NCR);
+
         registerFunction("abs", FUNCTION_ABS);
         registerFunction("exp", FUNCTION_EXP);
         registerFunction("ln", FUNCTION_LN);
         registerFunction("sqrt", FUNCTION_SQRT);
+
         registerFunction("sin", functionSin);
         registerFunction("cos", functionCos);
         registerFunction("tan", functionTan);
         registerFunction("sec", functionSec);
         registerFunction("csc", functionCsc);
         registerFunction("cot", functionCot);
+
+        registerFunction("arcsin", functionArcsin);
+        registerFunction("arccos", functionArccos);
+        registerFunction("arctan", functionArctan);
+        registerFunction("arcsec", functionArcsec);
+        registerFunction("arccsc", functionArccsc);
+        registerFunction("arccot", functionArccot);
+
+        registerFunction("random_int", FUNCTION_RAND_INT);
+
+        registerDocumentation(new Documentation("abs", "Absolute Value", "Finds the distance " +
+                "from zero of a number.", "Given a number, this function finds the distance form " +
+                "zero of a number, effectively turning negative numbers into positive ones.\n\n" +
+                "Example: abs(-2) -> 2", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("exp", "Exponentiate", "Brings e to the given power.",
+                "This function evaluates e to the power of the given value, and is the inverse " +
+                        "of the natural logarithm.\n\n" +
+                        "Example: exp(1) -> 2.718...", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("ln", "Natural Logarithm", "Gets the natural " +
+                "logarithm of the given value.", "The natural logarithm of a number is " +
+                "the power that e has to be brought to to be equal to the number.\n\n" +
+                "Example: ln(2.718) -> 1", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("sqrt", "Square Root", "Finds the square root " +
+                "of the number.", "A square root a of a number is defined as the non-negative a such that a times a is equal " +
+                "to that number.\n\n" +
+                "Example: sqrt(4) -> 2", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("sin", "Sine", "Computes the sine of the given angle, " +
+                "in radians.", "Example: sin(pi/6) -> 0.5", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("cos", "Cosine", "Computes the cosine of the given angle, " +
+                "in radians.", "Example: cos(pi/6) -> 0.866... (the exact result is sqrt(3)/2)", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("tan", "Tangent", "Computes the tangent of the given angle, " +
+                "in radians.", "Example: tan(pi/6) -> 0.577... (the exact result is 1/sqrt(3))", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("sec", "Secant", "Computes the secant of the given angle, " +
+                "in radians.", "Example: sec(pi/6) -> 1.154... (the exact result is 2/sqrt(3))", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("csc", "Cosecant", "Computes the cosecant of the given angle, " +
+                "in radians.", "Example: csc(pi/6) -> 2", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("cot", "Cotangent", "Computes the cotangent of the given angle, " +
+                "in radians.", "Example: cot(pi/6) -> 1.732... (the exact result is sqrt(3))", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("random_int", "Random Integer", "Generates a random integer [0, n].",
+                "Generates a pseudorandom number using the standard JVM random mechanism, keeping it less than or " +
+                        "equal to the given number.\n\n" +
+                        "Example: random_int(5) -> 4\n" +
+                        "random_int(5) -> 3\n" +
+                        "random_int(5) -> 3\n", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("arcsin", "Arcsine", "Computes the arcsine of x. (The result is in radians.)",
+                "Example: arcsin(0.5) -> 0.523... (the exact result is pi/6)", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("arccos", "Arccosine", "Computes the arccosine of x. (The result is in radians.)",
+                "Example: arccos(0.5) -> 1.047... (the exact result is pi/3)", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("arctan", "Arctangent", "Computes the arctangent of x. (The result is in radians.)",
+                "Example: arctan(1) -> 0.785... (the exact result is pi/4)", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("arcsec", "Arcsecant", "Computes the arcsecant of x. (The result is in radians.)",
+                "Example: arcsec(2) -> 1.047... (the exact result is pi/3)", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("arccsc", "Arccosecant", "Computes the arcscosecant of x. (The result is in radians.)",
+                "Example: arccsc(2) -> 0.523... (the exact result is pi/6)", DocumentationType.FUNCTION));
+        registerDocumentation(new Documentation("arccot", "Arccotangent", "Computes the arccotangent of x. (The result is in radians," +
+                " in the range (0, pi).)",
+                "Example: arccot(0) -> 1.570... (the exact result is pi/2)", DocumentationType.FUNCTION));
     }
 
     @Override

core/src/main/kotlin/org/nwapw/abacus/function/Documentation.kt

@@ -0,0 +1,26 @@
+package org.nwapw.abacus.function
+
+/**
+ * A data class used for storing information about a function.
+ *
+ * The Documentation class holds the information necessary to display the information
+ * about a function to the user.
+ *
+ * @param codeName the name of the function as it occurs in code.
+ * @param name the name of the function in English.
+ * @param description the short description of this function.
+ * @param longDescription the full description of this function.
+ * @param type the things this documentation maps to.
+ */
+data class Documentation(val codeName: String, val name: String,
+                         val description: String, val longDescription: String,
+                         val type: DocumentationType) {
+
+    fun matches(other: String): Boolean {
+        return codeName.toLowerCase().contains(other.toLowerCase()) ||
+                name.toLowerCase().contains(other.toLowerCase()) ||
+                description.toLowerCase().contains(other.toLowerCase()) ||
+                longDescription.toLowerCase().contains(other.toLowerCase())
+    }
+
+}

core/src/main/kotlin/org/nwapw/abacus/function/Operator.kt

@@ -0,0 +1,14 @@
+package org.nwapw.abacus.function
+
+/**
+ * A single operator that can be used by Abacus.
+ *
+ * This is a data class that holds the information about a single operator, such as a plus or minus.
+ *
+ * @param associativity the associativity of this operator, used for order of operations;.
+ * @param type the type of this operator, used for parsing (infix / prefix / postfix and binary / unary)
+ * @param precedence the precedence of this operator, used for order of operations.
+ * @param function the function this operator applies to its arguments.
+ */
+data class Operator(val associativity: OperatorAssociativity, val type: OperatorType,
+                    val precedence: Int, val function: Function)

core/src/main/kotlin/org/nwapw/abacus/tree/BinaryNode.kt

@@ -0,0 +1,26 @@
+package org.nwapw.abacus.tree
+
+/**
+ * A tree node that holds a binary operation.
+ *
+ * This node represents any binary operation, such as binary infix or binary postfix. The only
+ * currently implemented into Abacus is binary infix, but that has more to do with the parser than
+ * this class, which doesn't care about the order that its operation and nodes were found in text.
+ *
+ * @param operation the operation this node performs on its children.
+ * @param left the left node.
+ * @param right the right node.
+ */
+data class BinaryNode(val operation: String, val left: TreeNode? = null, val right: TreeNode?) : TreeNode() {
+
+    override fun <T : Any> reduce(reducer: Reducer<T>): T? {
+        val leftReduce = left?.reduce(reducer) ?: return null
+        val rightReduce = right?.reduce(reducer) ?: return null
+        return reducer.reduceNode(this, leftReduce, rightReduce)
+    }
+
+    override fun toString(): String {
+        return "(" + (left?.toString() ?: "null") + operation + (right?.toString() ?: "null") + ")"
+    }
+
+}

core/src/main/kotlin/org/nwapw/abacus/tree/FunctionNode.kt

@@ -0,0 +1,52 @@
+package org.nwapw.abacus.tree
+
+/**
+ * A tree node that holds a function call.
+ *
+ * The function call node can hold any number of children, and passes the to the appropriate reducer,
+ * but that is its sole purpose.
+ *
+ * @param function the function string.
+ */
+data class FunctionNode(val function: String) : TreeNode() {
+
+    /**
+     * List of function parameters added to this node.
+     */
+    val children: MutableList<TreeNode> = mutableListOf()
+
+    override fun <T : Any> reduce(reducer: Reducer<T>): T? {
+        val children = Array<Any>(children.size, { children[it].reduce(reducer) ?: return null; })
+        return reducer.reduceNode(this, *children)
+    }
+
+    override fun toString(): String {
+        val buffer = StringBuffer()
+        buffer.append(function)
+        buffer.append('(')
+        for (i in 0 until children.size) {
+            buffer.append(children[i].toString())
+            buffer.append(if (i == children.size - 1) ")" else ",")
+        }
+        return buffer.toString()
+    }
+
+    /**
+     * Appends a child to this node's list of children.
+     *
+     * @node the node to append.
+     */
+    fun appendChild(node: TreeNode){
+        children.add(node)
+    }
+
+    /**
+     * Prepends a child to this node's list of children.
+     *
+     * @node the node to prepend.
+     */
+    fun prependChild(node: TreeNode){
+        children.add(0, node)
+    }
+
+}

core/src/main/kotlin/org/nwapw/abacus/tree/NumberNode.kt

@@ -0,0 +1,23 @@
+package org.nwapw.abacus.tree
+
+import org.nwapw.abacus.number.NumberInterface
+
+/**
+ * A tree node that holds a single number value.
+ *
+ * This is a tree node that holds a single NumberInterface, which represents any number,
+ * and is not defined during compile time.
+ *
+ * @number the number value of this node.
+ */
+data class NumberNode(val number: NumberInterface) : TreeNode() {
+
+    override fun <T : Any> reduce(reducer: Reducer<T>): T? {
+        return reducer.reduceNode(this)
+    }
+
+    override fun toString(): String {
+        return number.toString()
+    }
+
+}

core/src/main/kotlin/org/nwapw/abacus/tree/Reducer.kt

@@ -0,0 +1,19 @@
+package org.nwapw.abacus.tree
+
+/**
+ * Reducer interface that takes a tree and returns a single value.
+ *
+ * The reducer walks the tree, visiting the children first, converting them into
+ * a value, and then attempts to reduce the parent. Eventually, the single final value is returned.
+ */
+interface Reducer <out T> {
+
+    /**
+     * Reduces the given tree node, given its already reduced children.
+     *
+     * @param treeNode the tree node to reduce.
+     * @param children the list of children, of type T.
+     */
+    fun reduceNode(treeNode: TreeNode, vararg children: Any) : T?
+
+}

core/src/main/kotlin/org/nwapw/abacus/tree/TreeNode.kt

@@ -0,0 +1,10 @@
+package org.nwapw.abacus.tree
+
+/**
+ * A tree node.
+ */
+abstract class TreeNode {
+
+    abstract fun <T: Any> reduce(reducer: Reducer<T>) : T?
+
+}

core/src/main/kotlin/org/nwapw/abacus/tree/UnaryNode.kt

@@ -0,0 +1,23 @@
+package org.nwapw.abacus.tree
+
+/**
+ * A tree node that holds a unary operation.
+ *
+ * This node holds a single operator applied to a single parameter, and does not care
+ * whether the operation was found before or after the parameter in the text.
+ *
+ * @param operation the operation applied to the given node.
+ * @param applyTo the node to which the operation will be applied.
+ */
+data class UnaryNode(val operation: String, val applyTo: TreeNode? = null) : TreeNode() {
+
+    override fun <T : Any> reduce(reducer: Reducer<T>): T? {
+        val reducedChild = applyTo?.reduce(reducer) ?: return null
+        return reducer.reduceNode(this, reducedChild)
+    }
+
+    override fun toString(): String {
+        return "(" + (applyTo?.toString() ?: "null") + ")" + operation
+    }
+
+}

core/src/main/resources/abacus.fxml

@@ -57,6 +57,7 @@
                         <Button text="Apply" onAction="#performSave"/>
                         <Button text="Reload Plugins" onAction="#performReload"/>
                         <Button text="Apply and Reload" onAction="#performSaveAndReload"/>
+                        <Button text="Scan Plugins" onAction="#performScan"/>
                     </FlowPane>
                 </GridPane>
             </Tab>

core/src/test/java/org/nwapw/abacus/tests/CalculationTests.java

@@ -88,8 +88,8 @@ public class CalculationTests {
     public void testExp(){
         testOutput("exp0", "exp(0)", "1");
         testOutput("exp1", "exp(1)", "2.718281828459045235360287471352662497757247");
-        testOutput("exp300", "exp(300)", "19424263952412559365842088360176992193662086");
-        testOutput("exp300", "exp(300)", "19424263952412559365842088360176992193662086");
+        testOutput("exp300", "exp(300)", "1.9424263952412559365842088360176992193662086");
+        testOutput("exp(-500)", "exp((500)`)", "7.1245764067412855315491573771227552469277568");
     }
 
     @Test
@@ -99,6 +99,9 @@ public class CalculationTests {
         testOutput("2^1", "(2^1)", "2");
         testOutput("2^-1", "(2^(1)`)", "0.5");
         testOutput("2^50", "(2^50)", "112589990684262");
+        testOutput("7^(-sqrt2*17)", "(7^((sqrt(2)*17))`)", "4.81354609155297814551845300063563");
+        testEvalError("0^0", "(0^0)");
+        testEvalError("(-13)^.9999", "((13)`^0.9999)");
     }
 
 }

fx/build.gradle

@@ -0,0 +1,10 @@
+plugins {
+  id 'org.jetbrains.kotlin.jvm' version '1.1.3'
+}
+apply plugin: 'application'
+
+dependencies {
+  compile project(':core')
+}
+
+mainClassName = 'org.nwapw.abacus.fx.AbacusApplication'

fx/src/main/java/org/nwapw/abacus/fx/AbacusApplication.java

@@ -33,4 +33,9 @@ public class AbacusApplication extends Application {
         super.stop();
         controller.performStop();
     }
+
+    public static void main(String[] args){
+        launch(args);
+    }
+
 }

fx/src/main/java/org/nwapw/abacus/fx/AbacusController.java

@@ -7,6 +7,7 @@ import javafx.collections.FXCollections;
 import javafx.collections.ObservableList;
 import javafx.collections.transformation.FilteredList;
 import javafx.fxml.FXML;
+import javafx.scene.Node;
 import javafx.scene.control.*;
 import javafx.scene.control.cell.CheckBoxListCell;
 import javafx.scene.text.Text;
@@ -14,6 +15,8 @@ import javafx.util.Callback;
 import javafx.util.StringConverter;
 import org.nwapw.abacus.Abacus;
 import org.nwapw.abacus.config.Configuration;
+import org.nwapw.abacus.function.Documentation;
+import org.nwapw.abacus.function.DocumentationType;
 import org.nwapw.abacus.number.ComputationInterruptedException;
 import org.nwapw.abacus.number.NumberInterface;
 import org.nwapw.abacus.plugin.ClassFinder;
@@ -24,7 +27,10 @@ import org.nwapw.abacus.tree.TreeNode;
 
 import java.io.File;
 import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Comparator;
 import java.util.Set;
+import java.util.stream.Collectors;
 
 
 /**
@@ -97,7 +103,7 @@ public class AbacusController implements PluginListener {
     @FXML
     private TextField computationLimitField;
     @FXML
-    private ListView<String> functionListView;
+    private ListView<Documentation> functionListView;
     @FXML
     private TextField functionListSearchField;
 
@@ -120,11 +126,11 @@ public class AbacusController implements PluginListener {
     /**
      * The list of functions that are registered in the calculator.
      */
-    private ObservableList<String> functionList;
+    private ObservableList<Documentation> functionList;
     /**
      * The filtered list displayed to the user.
      */
-    private FilteredList<String> functionFilter;
+    private FilteredList<Documentation> functionFilter;
 
     /**
      * The abacus instance used for changing the plugin configuration.
@@ -216,7 +222,7 @@ public class AbacusController implements PluginListener {
         Callback<TableColumn<HistoryModel, String>, TableCell<HistoryModel, String>> cellFactory =
                 param -> new CopyableCell<>();
         Callback<ListView<ToggleablePlugin>, ListCell<ToggleablePlugin>> pluginCellFactory =
-                param -> new CheckBoxListCell<>(ToggleablePlugin::enabledProperty, new StringConverter<ToggleablePlugin>() {
+                param -> new CheckBoxListCell<>(ToggleablePlugin::getEnabledProperty, new StringConverter<ToggleablePlugin>() {
                     @Override
                     public String toString(ToggleablePlugin object) {
                         return object.getClassName().substring(object.getClassName().lastIndexOf('.') + 1);
@@ -224,15 +230,15 @@ public class AbacusController implements PluginListener {
 
                     @Override
                     public ToggleablePlugin fromString(String string) {
-                        return new ToggleablePlugin(true, string);
+                        return new ToggleablePlugin(string, true);
                     }
                 });
-
         functionList = FXCollections.observableArrayList();
         functionFilter = new FilteredList<>(functionList, (s) -> true);
         functionListView.setItems(functionFilter);
         functionListSearchField.textProperty().addListener((observable, oldValue, newValue) ->
-                functionFilter.setPredicate((newValue.length() == 0) ? ((s) -> true) : ((s) -> s.contains(newValue))));
+                functionFilter.setPredicate((newValue.length() == 0) ? ((s) -> true) : ((s) -> s.matches(newValue))));
+        functionListView.setCellFactory(param -> new DocumentationCell());
         historyData = FXCollections.observableArrayList();
         historyTable.setItems(historyData);
         numberImplementationOptions = FXCollections.observableArrayList();
@@ -243,11 +249,11 @@ public class AbacusController implements PluginListener {
         enabledPluginView.setItems(enabledPlugins);
         enabledPluginView.setCellFactory(pluginCellFactory);
         inputColumn.setCellFactory(cellFactory);
-        inputColumn.setCellValueFactory(cell -> cell.getValue().inputProperty());
+        inputColumn.setCellValueFactory(cell -> cell.getValue().getInputProperty());
         parsedColumn.setCellFactory(cellFactory);
-        parsedColumn.setCellValueFactory(cell -> cell.getValue().parsedProperty());
+        parsedColumn.setCellValueFactory(cell -> cell.getValue().getParsedProperty());
         outputColumn.setCellFactory(cellFactory);
-        outputColumn.setCellValueFactory(cell -> cell.getValue().outputProperty());
+        outputColumn.setCellValueFactory(cell -> cell.getValue().getOutputProperty());
         coreTabPane.getSelectionModel().selectedItemProperty().addListener((observable, oldValue, newValue) -> {
             if (oldValue.equals(settingsTab)) alertIfApplyNeeded(true);
         });
@@ -255,13 +261,7 @@ public class AbacusController implements PluginListener {
         abacus = new Abacus(new Configuration(CONFIG_FILE));
         PluginManager abacusPluginManager = abacus.getPluginManager();
         abacusPluginManager.addListener(this);
-        abacusPluginManager.addInstantiated(new StandardPlugin(abacus.getPluginManager()));
-        try {
-            ClassFinder.loadJars("plugins").forEach(abacusPluginManager::addClass);
-        } catch (IOException | ClassNotFoundException e) {
-            e.printStackTrace();
-        }
-        abacusPluginManager.reload();
+        performScan();
 
         computationLimitField.setText(Double.toString(abacus.getConfiguration().getComputationDelay()));
         computationLimitField.textProperty().addListener((observable, oldValue, newValue) -> {
@@ -311,6 +311,19 @@ public class AbacusController implements PluginListener {
         reloadAlertShown = false;
     }
 
+    @FXML
+    public void performScan(){
+        PluginManager abacusPluginManager = abacus.getPluginManager();
+        abacusPluginManager.removeAll();
+        abacusPluginManager.addInstantiated(new StandardPlugin(abacus.getPluginManager()));
+        try {
+            ClassFinder.loadJars("plugins").forEach(abacusPluginManager::addClass);
+        } catch (IOException | ClassNotFoundException e) {
+            e.printStackTrace();
+        }
+        abacusPluginManager.reload();
+    }
+
     @FXML
     public void performReload() {
         alertIfApplyNeeded(true);
@@ -343,12 +356,14 @@ public class AbacusController implements PluginListener {
         numberImplementationBox.getSelectionModel().select(toSelect);
         for (Class<?> pluginClass : abacus.getPluginManager().getLoadedPluginClasses()) {
             String fullName = pluginClass.getName();
-            ToggleablePlugin plugin = new ToggleablePlugin(!disabledPlugins.contains(fullName), fullName);
-            plugin.enabledProperty().addListener(e -> changesMade = true);
+            ToggleablePlugin plugin = new ToggleablePlugin(fullName, !disabledPlugins.contains(fullName));
+            plugin.getEnabledProperty().addListener(e -> changesMade = true);
             enabledPlugins.add(plugin);
         }
-        functionList.addAll(manager.getAllFunctions());
-        functionList.sort(String::compareTo);
+        PluginManager pluginManager = abacus.getPluginManager();
+        functionList.addAll(manager.getAllFunctions().stream().map(name -> pluginManager.documentationFor(name, DocumentationType.FUNCTION))
+                .collect(Collectors.toCollection(ArrayList::new)));
+        functionList.sort(Comparator.comparing(Documentation::getCodeName));
     }
 
     @Override

fx/src/main/java/org/nwapw/abacus/fx/DocumentationCell.java

@@ -0,0 +1,59 @@
+package org.nwapw.abacus.fx;
+
+import javafx.scene.control.Label;
+import javafx.scene.control.ListCell;
+import javafx.scene.control.TitledPane;
+import javafx.scene.layout.VBox;
+import org.nwapw.abacus.function.Documentation;
+
+public class DocumentationCell extends ListCell<Documentation> {
+
+    private Label codeNameLabel;
+    private Label nameLabel;
+    private Label description;
+    private Label longDescription;
+    private TitledPane titledPane;
+
+    public DocumentationCell(){
+        VBox vbox = new VBox();
+        vbox.setSpacing(10);
+        titledPane = new TitledPane();
+        codeNameLabel = new Label();
+        nameLabel = new Label();
+        description = new Label();
+        longDescription = new Label();
+        codeNameLabel.setWrapText(true);
+        nameLabel.setWrapText(true);
+        description.setWrapText(true);
+        longDescription.setWrapText(true);
+        vbox.getChildren().add(codeNameLabel);
+        vbox.getChildren().add(nameLabel);
+        vbox.getChildren().add(description);
+        vbox.getChildren().add(longDescription);
+        titledPane.textProperty().bindBidirectional(codeNameLabel.textProperty());
+        titledPane.setContent(vbox);
+        titledPane.setExpanded(false);
+        titledPane.prefWidthProperty().bind(widthProperty().subtract(32));
+
+        visibleProperty().addListener((a, b, c) -> titledPane.setExpanded(false));
+    }
+
+    @Override
+    protected void updateItem(Documentation item, boolean empty) {
+        super.updateItem(item, empty);
+        if(empty){
+            codeNameLabel.setText("");
+            nameLabel.setText("");
+            description.setText("");
+            longDescription.setText("");
+            setGraphic(null);
+        } else {
+            codeNameLabel.setText(item.getCodeName());
+            nameLabel.setText(item.getName());
+            description.setText(item.getDescription());
+            longDescription.setText(item.getLongDescription());
+            setGraphic(titledPane);
+        }
+        titledPane.setExpanded(false);
+    }
+}

fx/src/main/kotlin/org/nwapw/abacus/fx/HistoryModel.kt

@@ -0,0 +1,32 @@
+package org.nwapw.abacus.fx
+
+import javafx.beans.property.SimpleStringProperty
+
+/**
+ * A model representing an input / output in the calculator.
+ *
+ * The HistoryModel class stores a record of a single user-provided input,
+ * its parsed form as it was interpreted by the calculator, and the output
+ * that was provided by the calculator. These are represented as properties
+ * to allow easy access by JavaFX cells.
+ *
+ * @param input the user input
+ * @param parsed the parsed version of the input.
+ * @param output the output string.
+ */
+class HistoryModel(input: String, parsed: String, output: String){
+
+    /**
+     * The property that holds the input.
+     */
+    val inputProperty = SimpleStringProperty(input)
+    /**
+     * The property that holds the parsed input.
+     */
+    val parsedProperty = SimpleStringProperty(parsed)
+    /**
+     * The property that holds the output.
+     */
+    val outputProperty = SimpleStringProperty(output)
+
+}

fx/src/main/kotlin/org/nwapw/abacus/fx/ToggleablePlugin.kt

@@ -0,0 +1,31 @@
+package org.nwapw.abacus.fx
+
+import javafx.beans.property.SimpleBooleanProperty
+
+/**
+ * A model representing a plugin that can be disabled or enabled.
+ *
+ * ToggleablePlugin is a model that is used to present to the user the option
+ * of disabling / enabling plugins. The class name in this plugin is stored if
+ * its "enabledPropery" is false, essentially blacklisting the plugin.
+ *
+ * @param className the name of the class that this model concerns.
+ * @param enabled whether or not the model should start enabled.
+ */
+class ToggleablePlugin (val className: String, enabled: Boolean) {
+
+    /**
+     * The property used to interact with JavaFX components.
+     */
+    val enabledProperty = SimpleBooleanProperty(enabled)
+
+    /**
+     * Checks whether this plugin is currently enabled or not.
+     *
+     * @return true if it is enabled, false otherwise.
+     */
+    fun isEnabled(): Boolean {
+        return enabledProperty.value
+    }
+
+}

settings.gradle

@@ -1 +1,2 @@
 rootProject.name = 'abacus'
+include 'core', 'fx'

src/main/java/org/nwapw/abacus/function/Operator.java

@@ -1,76 +0,0 @@
-package org.nwapw.abacus.function;
-
-/**
- * A class that represents a single infix operator.
- */
-public class Operator {
-
-    /**
-     * The associativity of the operator.
-     */
-    private OperatorAssociativity associativity;
-    /**
-     * The type of this operator.
-     */
-    private OperatorType type;
-    /**
-     * The precedence of the operator.
-     */
-    private int precedence;
-    /**
-     * The function that is called by this operator.
-     */
-    private Function function;
-
-    /**
-     * Creates a new operator with the given parameters.
-     *
-     * @param associativity the associativity of the operator.
-     * @param operatorType  the type of this operator, like binary infix or unary postfix.
-     * @param precedence    the precedence of the operator.
-     * @param function      the function that the operator calls.
-     */
-    public Operator(OperatorAssociativity associativity, OperatorType operatorType, int precedence, Function function) {
-        this.associativity = associativity;
-        this.type = operatorType;
-        this.precedence = precedence;
-        this.function = function;
-    }
-
-    /**
-     * Gets the operator's associativity.
-     *
-     * @return the associativity.
-     */
-    public OperatorAssociativity getAssociativity() {
-        return associativity;
-    }
-
-    /**
-     * Gets the operator's type.
-     *
-     * @return the type.
-     */
-    public OperatorType getType() {
-        return type;
-    }
-
-    /**
-     * Gets the operator's precedence.
-     *
-     * @return the precedence.
-     */
-    public int getPrecedence() {
-        return precedence;
-    }
-
-    /**
-     * Gets the operator's function.
-     *
-     * @return the function.
-     */
-    public Function getFunction() {
-        return function;
-    }
-
-}

src/main/java/org/nwapw/abacus/fx/HistoryModel.java

@@ -1,97 +0,0 @@
-package org.nwapw.abacus.fx;
-
-import javafx.beans.property.SimpleStringProperty;
-import javafx.beans.property.StringProperty;
-
-/**
- * The data model used for storing history entries.
- */
-public class HistoryModel {
-
-    /**
-     * The property used for displaying the column
-     * for the user input.
-     */
-    private final StringProperty input;
-    /**
-     * The property used for displaying the column
-     * that contains the parsed input.
-     */
-    private final StringProperty parsed;
-    /**
-     * The property used for displaying the column
-     * that contains the program output.
-     */
-    private final StringProperty output;
-
-    /**
-     * Creates a new history model with the given variables.
-     *
-     * @param input  the user input
-     * @param parsed the parsed input
-     * @param output the program output.
-     */
-    public HistoryModel(String input, String parsed, String output) {
-        this.input = new SimpleStringProperty();
-        this.parsed = new SimpleStringProperty();
-        this.output = new SimpleStringProperty();
-        this.input.setValue(input);
-        this.parsed.setValue(parsed);
-        this.output.setValue(output);
-    }
-
-    /**
-     * Gets the input property.
-     *
-     * @return the input property.
-     */
-    public StringProperty inputProperty() {
-        return input;
-    }
-
-    /**
-     * Gets the input.
-     *
-     * @return the input.
-     */
-    public String getInput() {
-        return input.get();
-    }
-
-    /**
-     * Gets the parsed input property.
-     *
-     * @return the parsed input property.
-     */
-    public StringProperty parsedProperty() {
-        return parsed;
-    }
-
-    /**
-     * Gets the parsed input.
-     *
-     * @return the parsed input.
-     */
-    public String getParsed() {
-        return parsed.get();
-    }
-
-    /**
-     * Gets the output property.
-     *
-     * @return the output property.
-     */
-    public StringProperty outputProperty() {
-        return output;
-    }
-
-    /**
-     * Gets the program output.
-     *
-     * @return the output.
-     */
-    public String getOutput() {
-        return output.get();
-    }
-
-}

src/main/java/org/nwapw/abacus/fx/ToggleablePlugin.java

@@ -1,60 +0,0 @@
-package org.nwapw.abacus.fx;
-
-import javafx.beans.property.BooleanProperty;
-import javafx.beans.property.SimpleBooleanProperty;
-
-/**
- * Class that represents an entry in the plugin check box list.
- * The changes from this property are written to the config on application.
- */
-public class ToggleablePlugin {
-
-    /**
-     * The property that determines whether the plugin will be enabled.
-     */
-    private final BooleanProperty enabled;
-    /**
-     * The name of the class this entry toggles.
-     */
-    private final String className;
-
-    /**
-     * Creates a new toggleable plugin with the given properties.
-     *
-     * @param enabled   the enabled / disabled state at the beginning.
-     * @param className the name of the class this plugin toggles.
-     */
-    public ToggleablePlugin(boolean enabled, String className) {
-        this.enabled = new SimpleBooleanProperty();
-        this.enabled.setValue(enabled);
-        this.className = className;
-    }
-
-    /**
-     * Gets the enabled property of this plugin.
-     *
-     * @return the enabled property.
-     */
-    public BooleanProperty enabledProperty() {
-        return enabled;
-    }
-
-    /**
-     * Checks if this plugin entry should be enabled.
-     *
-     * @return whether this plugin will be enabled.
-     */
-    public boolean isEnabled() {
-        return enabled.get();
-    }
-
-    /**
-     * Gets the class name this plugin toggles.
-     *
-     * @return the class name that should be disabled.
-     */
-    public String getClassName() {
-        return className;
-    }
-
-}

src/main/java/org/nwapw/abacus/tree/BinaryNode.java

@@ -1,108 +0,0 @@
-package org.nwapw.abacus.tree;
-
-/**
- * A tree node that represents an operation being applied to two operands.
- */
-public class BinaryNode extends TreeNode {
-
-    /**
-     * The operation being applied.
-     */
-    private String operation;
-    /**
-     * The left node of the operation.
-     */
-    private TreeNode left;
-    /**
-     * The right node of the operation.
-     */
-    private TreeNode right;
-
-    private BinaryNode() {
-    }
-
-    /**
-     * Creates a new operation node with the given operation
-     * and no child nodes.
-     *
-     * @param operation the operation.
-     */
-    public BinaryNode(String operation) {
-        this(operation, null, null);
-    }
-
-    /**
-     * Creates a new operation node with the given operation
-     * and child nodes.
-     *
-     * @param operation the operation.
-     * @param left      the left node of the expression.
-     * @param right     the right node of the expression.
-     */
-    public BinaryNode(String operation, TreeNode left, TreeNode right) {
-        this.operation = operation;
-        this.left = left;
-        this.right = right;
-    }
-
-    /**
-     * Gets the operation in this node.
-     *
-     * @return the operation in this node.
-     */
-    public String getOperation() {
-        return operation;
-    }
-
-    /**
-     * Gets the left sub-expression of this node.
-     *
-     * @return the left node.
-     */
-    public TreeNode getLeft() {
-        return left;
-    }
-
-    /**
-     * Sets the left sub-expression of this node.
-     *
-     * @param left the sub-expression to apply.
-     */
-    public void setLeft(TreeNode left) {
-        this.left = left;
-    }
-
-    /**
-     * Gets the right sub-expression of this node.
-     *
-     * @return the right node.
-     */
-    public TreeNode getRight() {
-        return right;
-    }
-
-    /**
-     * Sets the right sub-expression of this node.
-     *
-     * @param right the sub-expression to apply.
-     */
-    public void setRight(TreeNode right) {
-        this.right = right;
-    }
-
-    @Override
-    public <T> T reduce(Reducer<T> reducer) {
-        T leftReduce = left.reduce(reducer);
-        T rightReduce = right.reduce(reducer);
-        if (leftReduce == null || rightReduce == null) return null;
-        return reducer.reduceNode(this, leftReduce, rightReduce);
-    }
-
-    @Override
-    public String toString() {
-        String leftString = left != null ? left.toString() : "null";
-        String rightString = right != null ? right.toString() : "null";
-
-        return "(" + leftString + operation + rightString + ")";
-    }
-}

src/main/java/org/nwapw/abacus/tree/FunctionNode.java

@@ -1,85 +0,0 @@
-package org.nwapw.abacus.tree;
-
-import java.util.ArrayList;
-import java.util.List;
-
-/**
- * A node that represents a function call.
- */
-public class FunctionNode extends TreeNode {
-
-    /**
-     * The name of the function being called
-     */
-    private String function;
-    /**
-     * The list of arguments to the function.
-     */
-    private List<TreeNode> children;
-
-    /**
-     * Creates a function node with no function.
-     */
-    private FunctionNode() {
-    }
-
-    /**
-     * Creates a new function node with the given function name.
-     *
-     * @param function the function name.
-     */
-    public FunctionNode(String function) {
-        this.function = function;
-        children = new ArrayList<>();
-    }
-
-    /**
-     * Gets the function name for this node.
-     *
-     * @return the function name.
-     */
-    public String getFunction() {
-        return function;
-    }
-
-    /**
-     * Adds a child to the end of this node's child list.
-     *
-     * @param node the child to add.
-     */
-    public void appendChild(TreeNode node) {
-        children.add(node);
-    }
-
-    /**
-     * Adds a new child to the beginning of this node's child list.
-     *
-     * @param node the node to add.
-     */
-    public void prependChild(TreeNode node) {
-        children.add(0, node);
-    }
-
-    @Override
-    public <T> T reduce(Reducer<T> reducer) {
-        Object[] reducedChildren = new Object[children.size()];
-        for (int i = 0; i < reducedChildren.length; i++) {
-            reducedChildren[i] = children.get(i).reduce(reducer);
-            if (reducedChildren[i] == null) return null;
-        }
-        return reducer.reduceNode(this, reducedChildren);
-    }
-
-    @Override
-    public String toString() {
-        StringBuilder buffer = new StringBuilder();
-        buffer.append(function);
-        buffer.append("(");
-        for (int i = 0; i < children.size(); i++) {
-            buffer.append(children.get(i));
-            buffer.append(i == children.size() - 1 ? "" : ", ");
-        }
-        buffer.append(")");
-        return buffer.toString();
-    }
-}

src/main/java/org/nwapw/abacus/tree/NumberNode.java

@@ -1,49 +0,0 @@
-package org.nwapw.abacus.tree;
-
-import org.nwapw.abacus.number.NumberInterface;
-
-/**
- * A node implementation that represents a single number.
- */
-public class NumberNode extends TreeNode {
-
-    /**
-     * The number that is represented by this number node.
-     */
-    private NumberInterface number;
-
-    /**
-     * Creates a number node with no number.
-     */
-    public NumberNode() {
-        number = null;
-    }
-
-    /**
-     * Creates a new number node with the given double value.
-     *
-     * @param newNumber the number for which to create a number node.
-     */
-    public NumberNode(NumberInterface newNumber) {
-        this.number = newNumber;
-    }
-
-    /**
-     * Gets the number value of this node.
-     *
-     * @return the number value of this node.
-     */
-    public NumberInterface getNumber() {
-        return number;
-    }
-
-    @Override
-    public <T> T reduce(Reducer<T> reducer) {
-        return reducer.reduceNode(this);
-    }
-
-    @Override
-    public String toString() {
-        return number != null ? number.toString() : "null";
-    }
-}

src/main/java/org/nwapw/abacus/tree/Reducer.java

@@ -1,19 +0,0 @@
-package org.nwapw.abacus.tree;
-
-/**
- * Interface used to reduce a tree into a single value.
- *
- * @param <T> the value to reduce into.
- */
-public interface Reducer<T> {
-
-    /**
-     * Reduces the given tree into a single value of type T.
-     *
-     * @param node     the node being passed in to be reduced.
-     * @param children the already-reduced children of this node.
-     * @return the resulting value from the reduce.
-     */
-    public T reduceNode(TreeNode node, Object... children);
-
-}

src/main/java/org/nwapw/abacus/tree/TreeNode.java

@@ -1,17 +0,0 @@
-package org.nwapw.abacus.tree;
-
-/**
- * An abstract class that represents an expression tree node.
- */
-public abstract class TreeNode {
-
-    /**
-     * The function that reduces a tree to a single vale.
-     *
-     * @param reducer the reducer used to reduce the tree.
-     * @param <T>     the type the reducer produces.
-     * @return the result of the reduction, or null on error.
-     */
-    public abstract <T> T reduce(Reducer<T> reducer);
-
-}

src/main/java/org/nwapw/abacus/tree/UnaryNode.java

@@ -1,63 +0,0 @@
-package org.nwapw.abacus.tree;
-
-public class UnaryNode extends TreeNode {
-
-    /**
-     * The operation this node will apply.
-     */
-    private String operation;
-    /**
-     * The tree node to apply the operation to.
-     */
-    private TreeNode applyTo;
-
-    /**
-     * Creates a new node with the given operation and no child.
-     *
-     * @param operation the operation for this node.
-     */
-    public UnaryNode(String operation) {
-        this(operation, null);
-    }
-
-    /**
-     * Creates a new node with the given operation and child.
-     *
-     * @param operation the operation for this node.
-     * @param applyTo   the node to apply the function to.
-     */
-    public UnaryNode(String operation, TreeNode applyTo) {
-        this.operation = operation;
-        this.applyTo = applyTo;
-    }
-
-    @Override
-    public <T> T reduce(Reducer<T> reducer) {
-        Object reducedChild = applyTo.reduce(reducer);
-        if (reducedChild == null) return null;
-        return reducer.reduceNode(this, reducedChild);
-    }
-
-    /**
-     * Gets the operation of this node.
-     *
-     * @return the operation this node performs.
-     */
-    public String getOperation() {
-        return operation;
-    }
-
-    /**
-     * Gets the node to which this node's operation applies.
-     *
-     * @return the tree node to which the operation will be applied.
-     */
-    public TreeNode getApplyTo() {
-        return applyTo;
-    }
-
-    @Override
-    public String toString() {
-        return "(" + (applyTo == null ? "null" : applyTo.toString()) + ")" + operation;
-    }
-}

src/main/java/org/nwapw/abacus/window/HistoryTableModel.java

@@ -1,106 +0,0 @@
-package org.nwapw.abacus.window;
-
-import org.nwapw.abacus.tree.TreeNode;
-
-import javax.swing.table.AbstractTableModel;
-import java.util.ArrayList;
-import java.util.List;
-
-/**
- * A table model to store data about the history of inputs
- * in the calculator.
- */
-public class HistoryTableModel extends AbstractTableModel {
-
-    /**
-     * Static array used to get the column names.
-     */
-    public static final String[] COLUMN_NAMES = {
-            "Input",
-            "Parsed Input",
-            "Output"
-    };
-
-    /**
-     * Static array used to get the class of each column.
-     */
-    public static final Class[] CLASS_TYPES = {
-            String.class,
-            TreeNode.class,
-            String.class
-    };
-    /**
-     * The list of entries.
-     */
-    List<HistoryEntry> entries;
-
-    /**
-     * Creates a new empty history table model
-     */
-    public HistoryTableModel() {
-        entries = new ArrayList<>();
-    }
-
-    /**
-     * Adds an entry to the model.
-     *
-     * @param entry the entry to add.
-     */
-    public void addEntry(HistoryEntry entry) {
-        entries.add(entry);
-    }
-
-    @Override
-    public int getRowCount() {
-        return entries.size();
-    }
-
-    @Override
-    public int getColumnCount() {
-        return 3;
-    }
-
-    @Override
-    public String getColumnName(int columnIndex) {
-        return COLUMN_NAMES[columnIndex];
-    }
-
-    @Override
-    public Class<?> getColumnClass(int columnIndex) {
-        return CLASS_TYPES[columnIndex];
-    }
-
-    @Override
-    public boolean isCellEditable(int rowIndex, int columnIndex) {
-        return false;
-    }
-
-    @Override
-    public Object getValueAt(int rowIndex, int columnIndex) {
-        return entries.get(rowIndex).nthValue(columnIndex);
-    }
-
-    /**
-     * Class used specifically to hold data about
-     * the previous entries into the calculator.
-     */
-    public static class HistoryEntry {
-        public String input;
-        public TreeNode parsedInput;
-        public String output;
-
-        public HistoryEntry(String input, TreeNode parsedInput, String output) {
-            this.input = input;
-            this.parsedInput = parsedInput;
-            this.output = output;
-        }
-
-        Object nthValue(int n) {
-            if (n == 0) return input;
-            if (n == 1) return parsedInput;
-            if (n == 2) return output;
-            return null;
-        }
-    }
-
-}

src/main/java/org/nwapw/abacus/window/Window.java

@@ -1,255 +0,0 @@
-package org.nwapw.abacus.window;
-
-import org.nwapw.abacus.Abacus;
-import org.nwapw.abacus.number.NumberInterface;
-import org.nwapw.abacus.tree.TreeNode;
-
-import javax.swing.*;
-import java.awt.*;
-import java.awt.datatransfer.StringSelection;
-import java.awt.event.ActionListener;
-import java.awt.event.MouseAdapter;
-import java.awt.event.MouseEvent;
-
-/**
- * The main UI window for the calculator.
- */
-public class Window extends JFrame {
-
-    private static final String CALC_STRING = "Calculate";
-    private static final String SYNTAX_ERR_STRING = "Syntax Error";
-    private static final String EVAL_ERR_STRING = "Evaluation Error";
-    private static final String NUMBER_SYSTEM_LABEL = "Number Type:";
-    private static final String FUNCTION_LABEL = "Functions:";
-
-    /**
-     * Array of Strings to which the "calculate" button's text
-     * changes. For instance, in the graph tab, the name will
-     * be "Graph" and not "Calculate".
-     */
-    private static final String[] BUTTON_NAMES = {
-            CALC_STRING,
-            CALC_STRING
-    };
-
-    /**
-     * Array of booleans that determine whether the input
-     * field and the input button are enabled at a particular
-     * index.
-     */
-    private static boolean[] INPUT_ENABLED = {
-            true,
-            false
-    };
-
-    /**
-     * The instance of the Abacus class, used
-     * for interaction with plugins and configuration.
-     */
-    private Abacus abacus;
-    /**
-     * The last output by the calculator.
-     */
-    private String lastOutput;
-
-    /**
-     * The tabbed pane that separates calculator contexts.
-     */
-    private JTabbedPane pane;
-
-    /**
-     * The panel where the output occurs.
-     */
-    private JPanel calculationPanel;
-    /**
-     * The text area reserved for the last output.
-     */
-    private JTextArea lastOutputArea;
-    /**
-     * The table used for storing history results.
-     */
-    private JTable historyTable;
-    /**
-     * The table model used for managing history.
-     */
-    private HistoryTableModel historyModel;
-    /**
-     * The scroll pane for the history area.
-     */
-    private JScrollPane historyScroll;
-
-    /**
-     * The panel where the input occurs.
-     */
-    private JPanel inputPanel;
-    /**
-     * The input text field.
-     */
-    private JTextField inputField;
-    /**
-     * The "submit" button.
-     */
-    private JButton inputEnterButton;
-
-    /**
-     * The side panel for separate configuration.
-     */
-    private JPanel settingsPanel;
-    /**
-     * Panel for elements relating to number
-     * system selection.
-     */
-    private JPanel numberSystemPanel;
-    /**
-     * The possible list of number systems.
-     */
-    private JComboBox<String> numberSystemList;
-    /**
-     * The panel for elements relating to
-     * function selection.
-     */
-    private JPanel functionSelectPanel;
-    /**
-     * The list of functions available to the user.
-     */
-    private JComboBox<String> functionList;
-
-    /**
-     * Action listener that causes the input to be evaluated.
-     */
-    private ActionListener evaluateListener = (event) -> {
-        TreeNode parsedExpression = abacus.parseString(inputField.getText());
-        if (parsedExpression == null) {
-            lastOutputArea.setText(SYNTAX_ERR_STRING);
-            return;
-        }
-        NumberInterface numberInterface = abacus.evaluateTree(parsedExpression);
-        if (numberInterface == null) {
-            lastOutputArea.setText(EVAL_ERR_STRING);
-            return;
-        }
-        lastOutput = numberInterface.toString();
-        historyModel.addEntry(new HistoryTableModel.HistoryEntry(inputField.getText(), parsedExpression, lastOutput));
-        historyTable.invalidate();
-        lastOutputArea.setText(lastOutput);
-        inputField.setText("");
-    };
-
-    /**
-     * Array of listeners that tell the input button how to behave
-     * at a given input tab.
-     */
-    private ActionListener[] listeners = {
-            evaluateListener,
-            null
-    };
-
-    /**
-     * Creates a new window with the given manager.
-     *
-     * @param abacus the calculator instance to interact with other components.
-     */
-    public Window(Abacus abacus) {
-        this();
-        this.abacus = abacus;
-    }
-
-    /**
-     * Creates a new window.
-     */
-    private Window() {
-        super();
-
-        lastOutput = "";
-
-        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
-        setSize(320, 480);
-
-        inputField = new JTextField();
-        inputEnterButton = new JButton(CALC_STRING);
-
-        inputPanel = new JPanel();
-        inputPanel.setLayout(new BorderLayout());
-        inputPanel.add(inputField, BorderLayout.CENTER);
-        inputPanel.add(inputEnterButton, BorderLayout.SOUTH);
-
-        historyModel = new HistoryTableModel();
-        historyTable = new JTable(historyModel);
-        historyScroll = new JScrollPane(historyTable);
-        lastOutputArea = new JTextArea(lastOutput);
-        lastOutputArea.setEditable(false);
-
-        calculationPanel = new JPanel();
-        calculationPanel.setLayout(new BorderLayout());
-        calculationPanel.add(historyScroll, BorderLayout.CENTER);
-        calculationPanel.add(lastOutputArea, BorderLayout.SOUTH);
-
-        numberSystemList = new JComboBox<>();
-
-        numberSystemPanel = new JPanel();
-        numberSystemPanel.setAlignmentX(Component.LEFT_ALIGNMENT);
-        numberSystemPanel.setLayout(new FlowLayout());
-        numberSystemPanel.add(new JLabel(NUMBER_SYSTEM_LABEL));
-        numberSystemPanel.add(numberSystemList);
-        numberSystemPanel.setMaximumSize(numberSystemPanel.getPreferredSize());
-
-        functionList = new JComboBox<>();
-
-        functionSelectPanel = new JPanel();
-        functionSelectPanel.setAlignmentX(Component.LEFT_ALIGNMENT);
-        functionSelectPanel.setLayout(new FlowLayout());
-        functionSelectPanel.add(new JLabel(FUNCTION_LABEL));
-        functionSelectPanel.add(functionList);
-        functionSelectPanel.setMaximumSize(functionSelectPanel.getPreferredSize());
-
-        settingsPanel = new JPanel();
-        settingsPanel.setAlignmentX(Component.LEFT_ALIGNMENT);
-        settingsPanel.setLayout(new BoxLayout(settingsPanel, BoxLayout.PAGE_AXIS));
-        settingsPanel.add(numberSystemPanel);
-        settingsPanel.add(functionSelectPanel);
-
-        pane = new JTabbedPane();
-        pane.add("Calculator", calculationPanel);
-        pane.add("Settings", settingsPanel);
-        pane.addChangeListener(e -> {
-            int selectionIndex = pane.getSelectedIndex();
-            boolean enabled = INPUT_ENABLED[selectionIndex];
-            ActionListener listener = listeners[selectionIndex];
-            inputEnterButton.setText(BUTTON_NAMES[selectionIndex]);
-            inputField.setEnabled(enabled);
-            inputEnterButton.setEnabled(enabled);
-
-            for (ActionListener removingListener : inputEnterButton.getActionListeners()) {
-                inputEnterButton.removeActionListener(removingListener);
-                inputField.removeActionListener(removingListener);
-            }
-            if (listener != null) {
-                inputEnterButton.addActionListener(listener);
-                inputField.addActionListener(listener);
-            }
-        });
-        add(pane, BorderLayout.CENTER);
-        add(inputPanel, BorderLayout.SOUTH);
-
-        inputEnterButton.addActionListener(evaluateListener);
-        inputField.addActionListener(evaluateListener);
-        historyTable.addMouseListener(new MouseAdapter() {
-            @Override
-            public void mouseClicked(MouseEvent e) {
-                Point clickPoint = e.getPoint();
-                if (e.getClickCount() == 2) {
-                    int row = historyTable.rowAtPoint(clickPoint);
-                    int column = historyTable.columnAtPoint(clickPoint);
-                    String toCopy = historyTable.getValueAt(row, column).toString();
-                    Toolkit.getDefaultToolkit().getSystemClipboard().setContents(new StringSelection(toCopy), null);
-                }
-            }
-        });
-    }
-
-    @Override
-    public void setVisible(boolean b) {
-        super.setVisible(b);
-        if (b) inputField.requestFocusInWindow();
-    }
-}