Add the list of number interface providers to Plugins.

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

@@ -29,6 +29,10 @@ public abstract class Plugin {
      * A hash map of operators mapped to their string names.
      */
     private Map<String, Class<? extends NumberInterface>> numbers;
+    /**
+     * A hash map of constant providers for each number type.
+     */
+    private Map<Class<?>, java.util.function.Function<String, NumberInterface>> constantProviders;
     /**
      * The plugin manager in which to search for functions
      * not inside this package,
@@ -52,6 +56,7 @@ public abstract class Plugin {
         functions = new HashMap<>();
         operators = new HashMap<>();
         numbers = new HashMap<>();
+        constantProviders = new HashMap<>();
         enabled = false;
     }
 
@@ -82,6 +87,14 @@ public abstract class Plugin {
         return numbers.keySet();
     }
 
+    /**
+     * Gets the list of all constant providers provided by this plugin.
+     * @return the list of constant providers.
+     */
+    public final Set<Class<?>> providedConstantProviders() {
+        return constantProviders.keySet();
+    }
+
     /**
      * Gets a function under the given function name.
      *
@@ -112,6 +125,16 @@ public abstract class Plugin {
         return numbers.get(numberName);
     }
 
+    /**
+     * Gets the constant provider for the given class.
+     *
+     * @param pluginClass the class for which to provide constants.
+     * @return the provider, or null, if the plugin doesn't provide it.
+     */
+    public final java.util.function.Function<String, NumberInterface> getConstantProvider(Class<?> pluginClass){
+        return constantProviders.get(pluginClass);
+    }
+
     /**
      * Enables the function, loading the necessary instances
      * of functions.
@@ -131,6 +154,8 @@ public abstract class Plugin {
         onDisable();
         functions.clear();
         operators.clear();
+        numbers.clear();
+        constantProviders.clear();
         enabled = false;
     }
 
@@ -170,6 +195,19 @@ public abstract class Plugin {
         numbers.put(name, toRegister);
     }
 
+    /**
+     * To be used in load(). Registers a constant provider
+     * with the plugin internally, which makes it possible
+     * for the calculations to look up constants for each different
+     * number type.
+     * @param providerFor the class the provider works with.
+     * @param constantProvider the provider to register.
+     */
+    protected final void registerConstantProvider(Class<?> providerFor,
+                                                   java.util.function.Function<String, NumberInterface> constantProvider) {
+        constantProviders.put(providerFor, constantProvider);
+    }
+
     /**
      * Searches the PluginManager for the given function name.
      * This can be used by the plugins internally in order to call functions
@@ -194,6 +232,30 @@ public abstract class Plugin {
         return manager.operatorFor(name);
     }
 
+    /**
+     * Searches the PluginManager for the given number implementation.
+     * This can be used by the plugins internally in order to
+     * find classes by name that they do not provide.
+     *
+     * @param name the name for which to search
+     * @return the resulting number class.
+     */
+    protected final Class<? extends NumberInterface> numberFor(String name) {
+        return manager.numberFor(name);
+    }
+
+    /**
+     * Searches the PluginManager for the given constant provider.
+     * This can be used by the plugins internally in order
+     * to find constant providers for number provider they do not provide.
+     *
+     * @param forClass the class for which to get a generator for.
+     * @return the resulting generator
+     */
+    protected final java.util.function.Function<String, NumberInterface> constantProviderFor(Class<?> forClass){
+        return manager.constantProviderFor(forClass);
+    }
+
     /**
      * Abstract method to be overridden by plugin implementation, in which the plugins
      * are supposed to register the functions they provide and do any other

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

@@ -2,7 +2,6 @@ package org.nwapw.abacus.plugin;
 
 import org.nwapw.abacus.function.Function;
 import org.nwapw.abacus.function.Operator;
-import org.nwapw.abacus.number.NaiveNumber;
 import org.nwapw.abacus.number.NumberInterface;
 
 import java.lang.reflect.InvocationTargetException;
@@ -41,7 +40,7 @@ public class PluginManager {
      * List of registered constant providers for every
      * number class.
      */
-    private Map<Class<?>, java.util.function.Function<String, NaiveNumber>> cachedConstantProviders;
+    private Map<Class<?>, java.util.function.Function<String, NumberInterface>> cachedConstantProviders;
     /**
      * List of all functions loaded by the plugins.
      */
@@ -54,6 +53,10 @@ public class PluginManager {
      * List of all numbers loaded by the plugins.
      */
     private Set<String> allNumbers;
+    /**
+     * List of all the constant providers loaded by the plugins.
+     */
+    private Set<Class<?>> allConstantProviders;
     /**
      * The list of plugin listeners attached to this instance.
      */
@@ -72,6 +75,7 @@ public class PluginManager {
         allFunctions = new HashSet<>();
         allOperators = new HashSet<>();
         allNumbers = new HashSet<>();
+        allConstantProviders = new HashSet<>();
         listeners = new HashSet<>();
     }
 
@@ -87,6 +91,7 @@ public class PluginManager {
      * @param getFunction the function to get the T value under the given name
      * @param name        the name to search for
      * @param <T>         the type of element being search
+     * @param <K>         the type of key that the cache is indexed by.
      * @return the retrieved element, or null if it was not found.
      */
     private static <T, K> T searchCached(Collection<Plugin> plugins, Map<K, T> cache,
@@ -137,6 +142,15 @@ public class PluginManager {
         return searchCached(plugins, cachedNumbers, Plugin::providedNumbers, Plugin::getNumber, name);
     }
 
+    /**
+     * Gets the constant provider for the given class.
+     * @param forClass the class to get the provider for.
+     * @return the provider.
+     */
+    public java.util.function.Function<String, NumberInterface> constantProviderFor(Class<?> forClass){
+        return searchCached(plugins, cachedConstantProviders, Plugin::providedConstantProviders, Plugin::getConstantProvider, forClass);
+    }
+
     /**
      * Adds an instance of Plugin that already has been instantiated.
      *
@@ -172,6 +186,7 @@ public class PluginManager {
             allFunctions.addAll(plugin.providedFunctions());
             allOperators.addAll(plugin.providedOperators());
             allNumbers.addAll(plugin.providedNumbers());
+            allConstantProviders.addAll(plugin.providedConstantProviders());
         }
         listeners.forEach(e -> e.onLoad(this));
     }
@@ -184,6 +199,7 @@ public class PluginManager {
         allFunctions.clear();
         allOperators.clear();
         allNumbers.clear();
+        allConstantProviders.clear();
         listeners.forEach(e -> e.onUnload(this));
     }
 
@@ -222,6 +238,14 @@ public class PluginManager {
         return allNumbers;
     }
 
+    /**
+     * Gets all the constant providers loaded by the Plugin Manager.
+     * @return the set of all constant providers that were loaded.
+     */
+    public Set<Class<?>> getAllConstantProviders() {
+        return allConstantProviders;
+    }
+
     /**
      * Adds a plugin change listener to this plugin manager.
      *