Added lambda parsing.

src/ast.c

@@ -17,7 +17,9 @@ static char* asttype_names[] = {
     [AST_TYPE_BLOCK] = "BLOCK",
     [AST_TYPE_EXC] = "EXCEPTION",
     [AST_TYPE_FDEF] = "FUNCTION DEFINITION",
-    [AST_TYPE_ARG] = "DEFINITION ARGUMENT"
+    [AST_TYPE_ARG] = "DEFINITION ARGUMENT",
+    [AST_TYPE_LAMBDA] = "LAMBDA EXPRESSION"
+
 };
 
 AST* ast_init(ASTType type, void* data) {
@@ -58,6 +60,7 @@ void ast_destroy(AST* ast) {
         case AST_TYPE_BLOCK:  ast_block_data_destroy(ast->data); break;
         case AST_TYPE_FDEF:   ast_fdef_data_destroy(ast->data); break;
         case AST_TYPE_ARG:    ast_arg_data_destroy(ast->data); break;
+        case AST_TYPE_LAMBDA: ast_lambda_data_destroy(ast->data); break;
         default:
             log_dbgf("Unknown ast type %d (max: %d)", ast->type, AST_TYPE_MAX);
     }
@@ -81,6 +84,7 @@ void ast_destroy_psv(AST* ast) {
         case AST_TYPE_ARG:    ast_arg_data_destroy(ast->data); break;
         case AST_TYPE_BIF:    ast_bif_data_destroy(ast->data); break;
         case AST_TYPE_EXC:    ast_exc_data_destroy(ast->data); break;
+        case AST_TYPE_LAMBDA: ast_lambda_data_destroy(ast->data); break;
         default:
             log_dbgf("Unknown ast type %d (max: %d)", ast->type, AST_TYPE_MAX);
     }
@@ -111,6 +115,7 @@ void ast_print_i(AST* ast, int i) {
         case AST_TYPE_BLOCK:  ast_block_print(ast->data, i + 2); break;
         case AST_TYPE_FDEF:   ast_fdef_print(ast->data, i + 2); break;
         case AST_TYPE_ARG:    ast_arg_print(ast->data, i + 2); break;
+        case AST_TYPE_LAMBDA: ast_lambda_print(ast->data, i + 2); break;
         default:              exit(1);
     }
     INDENT_FIELD_NONL_END;
@@ -344,6 +349,32 @@ void ast_arg_print(ASTArgData* arg, int i) {
     INDENT_END;
 }
 
+ASTLambdaData* ast_lambda_data_init(size_t argc, AST** argv, AST* body) {
+    talloc(ASTLambdaData, lambda);
+
+    lambda->argc = argc;
+    lambda->argv = argv;
+    lambda->body = body;
+
+    return lambda;
+}
+
+void ast_lambda_data_destroy(ASTLambdaData* lambda) {
+    free(lambda->argv);
+    free(lambda);
+}
+
+void ast_lambda_print(ASTLambdaData* lambda, int i) {
+    INDENT_BEGIN(i)
+    INDENT_TITLE("ASTLambdaData", lambda);
+    INDENT_FIELD("argc", "%ld", lambda->argc);
+    INDENT_FIELD_LIST("argv", lambda->argv, lambda->argc, ast_print_i);
+    INDENT_FIELD_EXT_NONL_START("body");
+    ast_print_i(lambda->body, i + 2);
+    INDENT_FIELD_NONL_END;
+    INDENT_END;
+}
+
 AST* ast_find(Scope* scope, char* name) {
     while (scope) {
         AST* gotten = htab_get(scope->here, name);

src/grammar.y

@@ -47,6 +47,8 @@
 
 %token NL // Newline.
 
+%token BACKSLASH
+
 %left ADD SUB
 %left MUL DIV
 %precedence NEG
@@ -132,6 +134,15 @@ exp:
         $$ = ast_init(AST_TYPE_FDEF, ast_fdef_data_init($1, argc, argv, $5));
     }
 
+    // Lambda definitions.
+    | BACKSLASH GROUPS arg GROUPE exp {
+        size_t argc = $3->ln;
+        AST** argv = $3->buf;
+        argarr_destroypsv($3);
+        $$ = ast_init(AST_TYPE_LAMBDA, ast_lambda_data_init(argc, argv, $5));
+    }
+
+
     | BLOCKS block BLOCKE {
         $$ = ast_init(AST_TYPE_BLOCK, ast_block_data_init((AST**) $2->buf, $2->ln));
     }

src/include/ast.h

@@ -24,6 +24,7 @@ typedef enum {
     AST_TYPE_VREF,   // A variable reference.
     AST_TYPE_BLOCK,  // A block of code (scope).
     AST_TYPE_FDEF,   // A function definition.
+    AST_TYPE_LAMBDA, // An anonymous function definition.
     AST_TYPE_ARG,    // A definition argument.
     AST_TYPE_MAX = AST_TYPE_ARG,
 } ASTType;
@@ -71,7 +72,11 @@ void ast_exc_data_destroy(ASTExcData* exc);
 void ast_exc_print(ASTExcData*, int i);
 
 // arguments list as anonymous struct
-#define ARGS struct { size_t argc; AST** argv; }
+#define ARGS                                                                   \
+    struct {                                                                   \
+        size_t argc;                                                           \
+        AST** argv;                                                            \
+    }
 
 // A built-in function.
 typedef AST* (*ASTBIFData)(size_t argc, AST** argv, Scope* scope);
@@ -99,7 +104,7 @@ ASTCallData* ast_call_data_init(char* to, size_t argc, AST** argv);
 // Destroy an `ASTCallData` recursively.
 void ast_call_data_destroy(ASTCallData* call);
 // Destroy an `ASTCallData`.
-void ast_call_data_destroy_psv(ASTCallData *call);
+void ast_call_data_destroy_psv(ASTCallData* call);
 // Print an `ASTCallData`.
 void ast_call_print(ASTCallData*, int i);
 
@@ -141,7 +146,7 @@ ASTBlockData* ast_block_data_init(AST** inside, size_t ln);
 // Destroy an `ASTBlockData`, recursively.
 void ast_block_data_destroy(ASTBlockData* block);
 // Destroy an `ASTBlockData`.
-void ast_block_data_destroy_psv(ASTBlockData *block);
+void ast_block_data_destroy_psv(ASTBlockData* block);
 // Print an `ASTBlockData`.
 void ast_block_print(ASTBlockData*, int i);
 
@@ -179,7 +184,10 @@ typedef struct {
 
 // Creates a new `ASTLambdaData`.
 ASTLambdaData* ast_lambda_data_init(size_t argc, AST** argv, AST* body);
-// Destroy an `AST
+// Destroy an `ASTLambdaData`.
+void ast_lambda_data_destroy(ASTLambdaData*);
+// Print an `ASTLambdaData`.
+void ast_lambda_print(ASTLambdaData* arg, int i);
 
 // Find a name in the scope.
 AST* ast_find(Scope* scope, char* name);

src/lexer.c

@@ -116,6 +116,7 @@ int yylex() {
         case '{':  return BLOCKS;
         case '}':  return BLOCKE;
         case '=':  return EQ;
+        case '\\': return BACKSLASH;
         default:   fprintf(stderr, "Unexpected character: %c\n", c);
     }