Add hashtable for Environment tracking

1 files changed, 53 insertions, 0 deletions

diff --git a/src/parser.c b/src/parser.c
index 2215fad..e16fc4a 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -4,6 +4,15 @@
 static Object **objects = NULL;
 static Root *roots = NULL;
 
+
+uint64_t
+symbol_hash(const HashTable *table, void *key) {
+    Object *obj = key;
+    uint64_t hash = _xor_shift_hash(obj->text, array_size(obj->text));
+    hash = _fibonacci_hash(hash, table->shift_amount);
+    return hash;
+}
+
 Token
 peek_token(const Parser *parser) {
     return parser->tokens[parser->current];
@@ -391,6 +400,16 @@ parse(Token *tokens, Errors *errors) {
         array_push(roots, root);
     }
 
+    // TEST INSERTION/LOOKUP.
+    HashTable *table = ht_init(symbol_hash, object_equal);
+    ht_insert(table, &roots[0][0], &roots[1][0]);
+    ht_insert(table, &roots[2][0], &roots[3][0]);
+    Object *val = ht_lookup(table, &roots[2][0]);
+    object_display(val);
+    val = ht_lookup(table, &roots[0][0]);
+    object_display(val);
+    ht_free(table);
+
     // Perform semantic analysis.
     // TODO: Check that symbols are defined before usage.
     // TODO: Remove unnecessary statements.
@@ -522,3 +541,37 @@ object_display(Object *obj) {
     }
     return;
 }
+
+bool
+object_equal(Object *a, Object *b) {
+    if (a == NULL || b == NULL || a->type != b->type) {
+        return false;
+    }
+    switch (a->type) {
+        case OBJ_TYPE_TRUE:
+        case OBJ_TYPE_FALSE: {
+            return true;
+        } break;
+        case OBJ_TYPE_FIXNUM: {
+            return a->fixnum == b->fixnum;
+        } break;
+        case OBJ_TYPE_SYMBOL:
+        case OBJ_TYPE_STRING: {
+            if (array_size(a->text) != array_size(b->text)) {
+                return false;
+            }
+            for (size_t i = 0; i < array_size(a->text); i++) {
+                if (a->text[i] != b->text[i]) {
+                    return false;
+                }
+            }
+        } break;
+        case OBJ_TYPE_LAMBDA: {
+            // return a->closure == b.closure;
+        } break;
+        default: {
+            return false;
+        } break;
+    }
+    return true;
+}