Disallow empty bodies in control flow statements, added 'pass' keyword

Fixed #170
This commit is contained in:
2025-01-09 11:03:03 +11:00
parent 9de9c85bea
commit 90ffe9b40e
4 changed files with 28 additions and 17 deletions

View File

@@ -44,6 +44,7 @@ const Toy_KeywordTypeTuple keywordTuples[] = {
{TOY_TOKEN_KEYWORD_IMPORT, "import"},
{TOY_TOKEN_KEYWORD_IN, "in"},
{TOY_TOKEN_KEYWORD_OF, "of"},
{TOY_TOKEN_KEYWORD_PASS, "pass"},
{TOY_TOKEN_KEYWORD_PRINT, "print"},
{TOY_TOKEN_KEYWORD_RETURN, "return"},
{TOY_TOKEN_KEYWORD_TYPEAS, "typeas"},
@@ -404,12 +405,6 @@ void Toy_private_printToken(Toy_Token* token) {
return;
}
//read pass token, even though it isn't generated
if (token->type == TOY_TOKEN_PASS) {
printf(TOY_CC_NOTICE "PASS: \t%d\t%.*s\n" TOY_CC_RESET, (int)token->line, (int)token->length, token->lexeme);
return;
}
//print the line number
printf("\t%d\t%d\t", token->type, (int)token->line);

View File

@@ -156,6 +156,7 @@ static ParsingTuple parsingRulesetTable[] = {
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_IMPORT,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_IN,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_OF,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_PASS,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_PRINT,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_RETURN,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_TYPEAS,
@@ -221,7 +222,6 @@ static ParsingTuple parsingRulesetTable[] = {
{PREC_NONE,NULL,NULL},// TOY_TOKEN_OPERATOR_PIPE, // |
//meta tokens
{PREC_NONE,NULL,NULL},// TOY_TOKEN_PASS,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_ERROR,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_EOF,
};
@@ -730,7 +730,7 @@ static void makeExpr(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** ro
//forward declarations
static void makeBlockStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle);
static void makeDeclarationStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle);
static void makeDeclarationStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle, bool errorOnEmpty);
static void makeAssertStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
Toy_Ast* ast = NULL; //assert's emit function is a bit different
@@ -764,11 +764,11 @@ static void makeIfThenElseStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, To
consume(parser, TOY_TOKEN_OPERATOR_PAREN_RIGHT, "Expected ')' after 'if' condition");
// { thenBranch }
makeDeclarationStmt(bucketHandle, parser, &thenBranch);
makeDeclarationStmt(bucketHandle, parser, &thenBranch, true);
//else { elseBranch }
if (match(parser, TOY_TOKEN_KEYWORD_ELSE)) {
makeDeclarationStmt(bucketHandle, parser, &elseBranch);
makeDeclarationStmt(bucketHandle, parser, &elseBranch, true);
}
Toy_private_emitAstIfThenElse(bucketHandle, rootHandle, condBranch, thenBranch, elseBranch);
@@ -784,7 +784,7 @@ static void makeWhileStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast
consume(parser, TOY_TOKEN_OPERATOR_PAREN_RIGHT, "Expected ')' after 'while' condition");
// { thenBranch }
makeDeclarationStmt(bucketHandle, parser, &thenBranch);
makeDeclarationStmt(bucketHandle, parser, &thenBranch, true);
Toy_private_emitAstWhileThen(bucketHandle, rootHandle, condBranch, thenBranch);
}
@@ -899,8 +899,8 @@ static void makeStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** ro
return;
}
//empty lines
else if (match(parser, TOY_TOKEN_OPERATOR_SEMICOLON)) {
//empty lines, or pass statements
else if (match(parser, TOY_TOKEN_OPERATOR_SEMICOLON) || match(parser, TOY_TOKEN_KEYWORD_PASS)) {
Toy_private_emitAstPass(bucketHandle, rootHandle);
return;
}
@@ -913,9 +913,16 @@ static void makeStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** ro
}
}
static void makeDeclarationStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
static void makeDeclarationStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle, bool errorOnEmpty) {
//disallow empty control flow bodies
if (errorOnEmpty && match(parser, TOY_TOKEN_OPERATOR_SEMICOLON)) {
printError(parser, parser->previous, "Empty control flow bodies are disallowed, use the 'pass' keyword");
Toy_private_emitAstError(bucketHandle, rootHandle);
return;
}
//variable declarations
if (match(parser, TOY_TOKEN_KEYWORD_VAR)) {
else if (match(parser, TOY_TOKEN_KEYWORD_VAR)) {
makeVariableDeclarationStmt(bucketHandle, parser, rootHandle);
}
@@ -938,7 +945,7 @@ static void makeBlockStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast
while (parser->current.type != TOY_TOKEN_OPERATOR_BRACE_RIGHT && !match(parser, TOY_TOKEN_EOF)) {
//process the grammar rules
Toy_Ast* stmt = NULL;
makeDeclarationStmt(bucketHandle, parser, &stmt);
makeDeclarationStmt(bucketHandle, parser, &stmt, false);
//if something went wrong
if (parser->panic) {

View File

@@ -37,6 +37,7 @@ typedef enum Toy_TokenType {
TOY_TOKEN_KEYWORD_IMPORT,
TOY_TOKEN_KEYWORD_IN,
TOY_TOKEN_KEYWORD_OF,
TOY_TOKEN_KEYWORD_PASS,
TOY_TOKEN_KEYWORD_PRINT,
TOY_TOKEN_KEYWORD_RETURN,
TOY_TOKEN_KEYWORD_TYPEAS,
@@ -102,7 +103,6 @@ typedef enum Toy_TokenType {
TOY_TOKEN_OPERATOR_PIPE, // |
//meta tokens
TOY_TOKEN_PASS,
TOY_TOKEN_ERROR,
TOY_TOKEN_EOF,
} Toy_TokenType;