Add OP_DROP and improve error reporting

7 files changed, 33 insertions, 19 deletions

diff --git a/src/bytecode/compiler.h b/src/bytecode/compiler.h
index 6dab1fe..9fefd2a 100755
--- a/src/bytecode/compiler.h
+++ b/src/bytecode/compiler.h
@@ -504,6 +504,7 @@ compile(Token *tokens) {
     Token start_tok = peek_token(&compiler);
     while (has_next_token(&compiler) && peek_token(&compiler).type != TOKEN_EOF) {
         parse_tree(chunk, &compiler);
+        add_code(chunk, OP_DROP, start_tok.line, start_tok.column);
     }
     add_code(chunk, OP_RETURN, start_tok.line, start_tok.column);
     return chunk;
diff --git a/src/bytecode/debug.h b/src/bytecode/debug.h
index 1e0d4d6..8c4a2eb 100755
--- a/src/bytecode/debug.h
+++ b/src/bytecode/debug.h
@@ -39,6 +39,8 @@ static const char* ops_str[] = {
     // Procedures.
     [OP_CALL] = "OP_CALL",
     [OP_RETURN] = "OP_RETURN",
+    // Clear stack after each statement.
+    [OP_DROP] = "OP_DROP",
 };
 
 void
diff --git a/src/bytecode/errors.c b/src/bytecode/errors.c
index c2ab77f..b4595a1 100755
--- a/src/bytecode/errors.c
+++ b/src/bytecode/errors.c
@@ -29,3 +29,23 @@ error_push(Error error) {
         errors[errors_n++] = error;
     }
 }
+
+void
+report_errors(char *file_name) {
+    for (size_t i = 0; i < errors_n; i++) {
+        Error err = errors[i];
+        fprintf(stderr, "%s", file_name);
+        if (err.line != 0) {
+            fprintf(stderr, ":%ld:%ld", err.line, err.col);
+        }
+        switch (err.type) {
+            case ERR_TYPE_LEXER:    { fprintf(stderr, ": [lexer]");    } break;
+            case ERR_TYPE_COMPILER: { fprintf(stderr, ": [compiler]"); } break;
+            case ERR_TYPE_RUNTIME:  { fprintf(stderr, ": [runtime]");  } break;
+            case ERR_TYPE_PARSER:   { fprintf(stderr, ": [parser]");   } break;
+            default: break;
+        }
+        fprintf(stderr, " %s\n", error_msgs[err.value]);
+    }
+    errors_n = 0;
+}
diff --git a/src/bytecode/errors.h b/src/bytecode/errors.h
index 7b3446e..425c768 100755
--- a/src/bytecode/errors.h
+++ b/src/bytecode/errors.h
@@ -38,6 +38,7 @@ typedef struct Error {
 } Error;
 
 void error_push(Error error);
+void report_errors(char *file_name);
 
 #define ERR_MAX_NUMBER 16
 
diff --git a/src/bytecode/main.c b/src/bytecode/main.c
index 7cb0a2a..7f2042e 100755
--- a/src/bytecode/main.c
+++ b/src/bytecode/main.c
@@ -126,15 +126,7 @@ run_file(char *file_name) {
 
     // Check if there were any errors.
     if (errors_n != 0 && !supress_errors) {
-        for (size_t i = 0; i < errors_n; i++) {
-            Error err = errors[i];
-            fprintf(stderr, "%s", file_name);
-            if (err.line != 0) {
-                fprintf(stderr, ":%ld:%ld", err.line, err.col);
-            }
-            fprintf(stderr, ": %s\n", error_msgs[err.value]);
-        }
-        errors_n = 0;
+        report_errors(file_name);
     }
 
     free(source);
@@ -164,15 +156,7 @@ run_stdin(void) {
 
     // Check if there were any errors.
     if (errors_n != 0 && !supress_errors) {
-        for (size_t i = 0; i < errors_n; i++) {
-            Error err = errors[i];
-            fprintf(stderr, "stdin");
-            if (err.line != 0) {
-                fprintf(stderr, ":%ld:%ld", err.line, err.col);
-            }
-            fprintf(stderr, ": %s\n", error_msgs[err.value]);
-        }
-        errors_n = 0;
+        report_errors("stdin");
     }
 
     array_free(source);
diff --git a/src/bytecode/ops.h b/src/bytecode/ops.h
index d046ca2..7a43b91 100755
--- a/src/bytecode/ops.h
+++ b/src/bytecode/ops.h
@@ -33,6 +33,8 @@ typedef enum Ops {
     // Procedures.
     OP_CALL,
     OP_RETURN,
+    // Clear stack after each statement.
+    OP_DROP,
 } Ops;
 
 #endif // BDL_OPS_H
diff --git a/src/bytecode/vm.h b/src/bytecode/vm.h
index 63eedfa..d654e2c 100755
--- a/src/bytecode/vm.h
+++ b/src/bytecode/vm.h
@@ -64,7 +64,8 @@ vm_reset(VM *vm) {
         .value = ERR_WRONG_ARG_TYPE, \
         .line = frame->chunk->lines[vm->pc - frame->chunk->code - 1].line, \
         .col = frame->chunk->lines[vm->pc - frame->chunk->code - 1].col, \
-    })
+    }); \
+    return
 
 #define SYMBOL_NOT_FOUND_ERR() \
     error_push((Error){ \
@@ -268,6 +269,9 @@ vm_interpret(VM *vm) {
                 array_head(vm->frames)->size--;
                 frame = &vm->frames[array_size(vm->frames) - 1];
             } break;
+            case OP_DROP: {
+                array_head(vm->stack)->size = 0;
+            } break;
             default: {
                 error_push((Error){
                     .type = ERR_TYPE_RUNTIME,