Begin working on an initial implementation for the parser.

include/libabacus.h

@@ -9,7 +9,9 @@ enum libab_result {
     LIBAB_SUCCESS,
     LIBAB_MALLOC,
     LIBAB_BAD_PATTERN,
-    LIBAB_FAILED_MATCH
+    LIBAB_FAILED_MATCH,
+    LIBAB_EOF,
+    LIBAB_UNEXPECTED
 };
 
 typedef enum libab_result libab_result;

src/parser.c

@@ -1,3 +1,9 @@
+#include "libabacus.h"
+#include "parser.h"
+#include "libabacus_util.h"
+#include "lexer.h"
+#include <stdlib.h>
+
 struct parser_state {
     ll_node* current_node;
     lexer_match* current_match;
@@ -20,10 +26,56 @@ void _parser_state_step(struct parser_state* state) {
     }
     _parser_state_update(state);
 }
+
+int _parser_is_char(struct parser_state* state, char to_expect) {
+    return (state->current_match && state->current_match->type == TOKEN_CHAR &&
+            state->string[state->current_match->from] == to_expect);
+}
+
+int _parser_eof(struct parser_state* state) {
+    return state->current_match == NULL;
+}
+
+libab_result _parser_consume_char(struct parser_state* state, char to_consume) {
+    libab_result result = LIBAB_SUCCESS;
+    if(state->current_match == NULL) {
+        result = LIBAB_EOF;
+    } else if(state->current_match->type != TOKEN_CHAR ||
+            state->string[state->current_match->from] != to_consume) {
+        result = LIBAB_UNEXPECTED;
+    } else {
+        _parser_state_step(state);
+    }
+    return result;
+}
+
+libab_result _parse_block(struct parser_state* state,
+        tree** store_into, int expect_braces) {
+    libab_result result = LIBAB_SUCCESS;
+    *store_into = malloc(sizeof(**store_into));
+    if(*store_into == NULL) result = LIBAB_MALLOC;
+
+    if(expect_braces && result == LIBAB_SUCCESS) result = _parser_consume_char(state, '{');
+
+    while(result == LIBAB_SUCCESS && 
+            !_parser_eof(state) &&
+            !(expect_braces && _parser_is_char(state, '}'))) {
+
+    }
+
+    if(expect_braces && result == LIBAB_SUCCESS) result = _parser_consume_char(state, '}');
+    return result;
+}
+
 libab_result parse_tokens(ll* tokens, const char* string, tree** store_into) {
     libab_result result = LIBAB_SUCCESS;
     struct parser_state state;
     _parser_state_init(&state, tokens, string);
 
+    result = _parse_block(&state, store_into, 0);
+    if(result == LIBAB_SUCCESS) {
+        (*store_into)->variant = BASE;
+    } 
+
     return result;
 }