cparse.c now throws an error on illegal statements

This commit is contained in:
cpunch 2021-02-19 12:47:12 -06:00
parent 1eec23035f
commit 40739e9bea

View File

@ -84,8 +84,11 @@ typedef struct {
Precedence level;
} ParseRule;
static void parsePrecedence(CParseState*, Precedence);
// returns true if first prefix was ran
static bool parsePrecedence(CParseState*, Precedence);
// returns # of pushed values onto the stack
static int expressionPrecedence(CParseState *pstate, int needed, Precedence prec, bool forceNeeded);
// returns # of pushed values onto the stack
static int expression(CParseState *pstate, int needed, bool forceNeeded);
static void statement(CParseState *pstate);
static void declaration(CParseState *pstate);
@ -969,13 +972,14 @@ static ParseRule* getRule(CTokenType type) {
return &ruleTable[type];
}
static void parsePrecedence(CParseState *pstate, Precedence prec) {
// returns true if it got past the first token (aka prefix wasn't null)
static bool parsePrecedence(CParseState *pstate, Precedence prec) {
advance(pstate);
ParseFunc prefix = getRule(pstate->previous.type)->prefix;
if (prefix == NULL)
return;
return false;
bool canAssign = prec <= PREC_ASSIGNMENT;
prefix(pstate, canAssign, prec);
@ -989,6 +993,8 @@ static void parsePrecedence(CParseState *pstate, Precedence prec) {
if (canAssign && match(pstate, TOKEN_EQUAL)) {
error(pstate, "Invalid assignment!");
}
return true;
}
static void declareLocal(CParseState *pstate, bool forceLocal) {
@ -1588,9 +1594,21 @@ static void expressionStatement(CParseState *pstate) {
continueStatement(pstate);
} else if (match(pstate, TOKEN_RETURN)) {
returnStatement(pstate);
} else if (match(pstate, TOKEN_EOS)) {
// just consume the ';'
} else {
// cache expectedValues
int lastExpected = pstate->compiler->expectedValues;
pstate->compiler->expectedValues = 0;
// expression or assignment
expressionPrecedence(pstate, 0, PREC_ASSIGNMENT, false);
if (!parsePrecedence(pstate, PREC_ASSIGNMENT)) {
// we never processed anything :/
error(pstate, "Expected expresssion, statement or assignment!");
}
// restore previous expectedValues
pstate->compiler->expectedValues = lastExpected;
}
// realign the stack