hash map contains

6 files changed, 25 insertions, 7 deletions

diff --git a/include/program.h b/include/program.h
index 543b38d..075bfca 100644
--- a/include/program.h
+++ b/include/program.h
@@ -30,6 +30,7 @@
 #define AMAL_PROGRAM_INVALID_EXTERNAL_FUNCTIONS_SIZE -18
 #define AMAL_PROGRAM_INSTRUCTION_INVALID_EXTERN_FUNC_INDEX -19
 #define AMAL_PROGRAM_NO_SUCH_EXTERNAL_FUNCTION -20
+#define AMAL_PROGRAM_EXTERN_FUNC_ALREADY_EXISTS -21
 
 #define AMAL_PROGRAM_MAGIC_NUMBER (u32)0xdec05eba
 #define AMAL_PROGRAM_MAJOR_VERSION 1
@@ -66,6 +67,10 @@ typedef struct {
 CHECK_RESULT int amal_program_init(amal_program *self);
 void amal_program_deinit(amal_program *self);
 
+/*
+    returns @AMAL_PROGRAM_EXTERN_FUNC_ALREADY_EXISTS if a function with the name @name already exists
+    in the program
+*/
 CHECK_RESULT int amal_program_add_extern_func(amal_program *self, BufferView name, void *func_ptr, int args_byte_size);
 
 CHECK_RESULT int amal_program_append_bytecode(amal_program *self, Bytecode *bytecode);
diff --git a/include/std/hash_map.h b/include/std/hash_map.h
index d789db4..c9e5b51 100644
--- a/include/std/hash_map.h
+++ b/include/std/hash_map.h
@@ -25,15 +25,17 @@ struct HashMap {
 
 CHECK_RESULT int hash_map_init(HashMap *self, ArenaAllocator *allocator, usize value_type_size, HashMapCompare key_compare_func, HashMapHash key_hash_func);
 /*
-Not thread-safe.
-Expected @value size to be @self->value_type_size.
+    Not thread-safe.
+    Expected @value size to be @self->value_type_size.
 */
 CHECK_RESULT int hash_map_insert(HashMap *self, BufferView key, void *value);
 /*
-Thread-safe unless @hash_map_insert is used in another thread at the same time.
-Expected @value size to be @self->value_type_size.
+    Thread-safe unless @hash_map_insert is used in another thread at the same time.
+    Expected @value size to be @self->value_type_size.
+    If @value is NULL, then the value is not copied and the functions works the same as @hash_map_contains
 */
 CHECK_RESULT bool hash_map_get(HashMap *self, BufferView key, void *value);
+CHECK_RESULT bool hash_map_contains(HashMap *self, BufferView key);
 
 int hash_map_compare_string(const void *a, const void *b);
 
diff --git a/src/parser.c b/src/parser.c
index cdf7c5b..03b835e 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -521,7 +521,7 @@ static void parser_parse_else_if_statement_loop(Parser *self, IfStatement *if_st
         if(!next_else_if)
             break;
         else_if_stmt->next_else_if_stmt = next_else_if;
-        /* else statement, which because they have no conditions; can't be followed by another else statement */
+        /* else statement that has no condition can't be followed by another else statement */
         if(!else_if_stmt->condition)
             break;
         else_if_stmt = next_else_if;
diff --git a/src/program.c b/src/program.c
index 9ec1b41..17aee03 100644
--- a/src/program.c
+++ b/src/program.c
@@ -91,6 +91,10 @@ int amal_program_add_extern_func(amal_program *self, BufferView name, void *func
     ProgramExternFunc extern_func;
     extern_func.func = func_ptr;
     extern_func.args_byte_size = args_byte_size;
+
+    if(hash_map_contains(&self->extern_funcs_map, name))
+        return AMAL_PROGRAM_EXTERN_FUNC_ALREADY_EXISTS;
+
     return hash_map_insert(&self->extern_funcs_map, name, &extern_func);
 }
 
diff --git a/src/std/hash_map.c b/src/std/hash_map.c
index 2b29f2e..48e9e38 100644
--- a/src/std/hash_map.c
+++ b/src/std/hash_map.c
@@ -192,7 +192,8 @@ bool hash_map_get(HashMap *self, BufferView key, void *value) {
         BufferView bucket_key;
         bucket_key = bucket_node_get_key(bucket_node);
         if(hash == bucket_node_get_hash(bucket_node) && self->compare_func(&key, &bucket_key) == 0) {
-            am_memcpy(value, bucket_node_get_value(bucket_node), self->value_type_size);
+            if(value)
+                am_memcpy(value, bucket_node_get_value(bucket_node), self->value_type_size);
             return bool_true;
         }
     }
@@ -200,6 +201,10 @@ bool hash_map_get(HashMap *self, BufferView key, void *value) {
     return bool_false;
 }
 
+bool hash_map_contains(HashMap *self, BufferView key) {
+    return hash_map_get(self, key, NULL);
+}
+
 #define MIN(a, b) ((a) < (b) ? (a) : (b))
 
 int hash_map_compare_string(const void *a, const void *b) {
diff --git a/tests/bytecode.amal b/tests/bytecode.amal
index 096f921..0aad6de 100644
--- a/tests/bytecode.amal
+++ b/tests/bytecode.amal
@@ -4,10 +4,12 @@ extern const print_extern_num: fn(num: i32);
 const main = fn {
     var value = 23;
     value = 34;
-    const value2: i64 = 23;
+    const value2: i64 = 54;
     const value3 = 2 + 5 - 1 * 10 / 2;
     const str_value = "hello, world";
     print();
+    //if value2 == 54
+    //    const result = print_num(1337);
     const result = print_num(1337);
 }