static boolean[] isRightAssociative = new boolean[MAX_TOKEN + 1];
static {
isRightAssociative[ASSIGN] =
- isRightAssociative[ASSIGN_BITOR] =
- isRightAssociative[ASSIGN_BITXOR] =
- isRightAssociative[ASSIGN_BITAND] =
- isRightAssociative[ASSIGN_LSH] =
- isRightAssociative[ASSIGN_RSH] =
- isRightAssociative[ASSIGN_URSH] =
- isRightAssociative[ASSIGN_ADD] =
- isRightAssociative[ASSIGN_SUB] =
- isRightAssociative[ASSIGN_MUL] =
- isRightAssociative[ASSIGN_DIV] =
- isRightAssociative[ASSIGN_MOD] = true;
+ isRightAssociative[ASSIGN_BITOR] =
+ isRightAssociative[ASSIGN_BITXOR] =
+ isRightAssociative[ASSIGN_BITAND] =
+ isRightAssociative[ASSIGN_LSH] =
+ isRightAssociative[ASSIGN_RSH] =
+ isRightAssociative[ASSIGN_URSH] =
+ isRightAssociative[ASSIGN_ADD] =
+ isRightAssociative[ASSIGN_SUB] =
+ isRightAssociative[ASSIGN_MUL] =
+ isRightAssociative[ASSIGN_DIV] =
+ isRightAssociative[ASSIGN_MOD] = true;
precedence[ASSIGN] =
- precedence[ASSIGN_BITOR] =
- precedence[ASSIGN_BITXOR] =
- precedence[ASSIGN_BITAND] =
- precedence[ASSIGN_LSH] =
- precedence[ASSIGN_RSH] =
- precedence[ASSIGN_URSH] =
- precedence[ASSIGN_ADD] =
- precedence[ASSIGN_SUB] =
- precedence[ASSIGN_MUL] =
- precedence[ASSIGN_DIV] =
- precedence[ASSIGN_MOD] = 1;
+ precedence[ASSIGN_BITOR] =
+ precedence[ASSIGN_BITXOR] =
+ precedence[ASSIGN_BITAND] =
+ precedence[ASSIGN_LSH] =
+ precedence[ASSIGN_RSH] =
+ precedence[ASSIGN_URSH] =
+ precedence[ASSIGN_ADD] =
+ precedence[ASSIGN_SUB] =
+ precedence[ASSIGN_MUL] =
+ precedence[ASSIGN_DIV] =
+ precedence[ASSIGN_MOD] = 1;
precedence[HOOK] = 2;
precedence[COMMA] = 3;
precedence[OR] = precedence[AND] = 4;
/** gets a token and throws an exception if it is not <tt>code</tt> */
private void consume(int code) throws IOException {
- if (getToken() != code) throw new ParserException("expected " + codeToString[code] + ", got " + (op == -1 ? "EOF" : codeToString[op]));
+ if (getToken() != code) throw pe("expected " + codeToString[code] + ", got " + (op == -1 ? "EOF" : codeToString[op]));
}
/**
* appended bytecodes MUST grow the stack by exactly one element.
*/
private void startExpr(CompiledFunctionImpl appendTo, int minPrecedence) throws IOException {
- int saveParserLine = parserLine;
- _startExpr(appendTo, minPrecedence);
- parserLine = saveParserLine;
+ int saveParserLine = parserLine;
+ _startExpr(appendTo, minPrecedence);
+ parserLine = saveParserLine;
}
private void _startExpr(CompiledFunctionImpl appendTo, int minPrecedence) throws IOException {
int tok = getToken();
CompiledFunctionImpl b = appendTo;
switch (tok) {
- case -1: throw new ParserException("expected expression");
+ case -1: throw pe("expected expression");
// all of these simply push values onto the stack
case NUMBER: b.add(parserLine, LITERAL, number); break;
}
case INC: case DEC: { // prefix (not postfix)
startExpr(b, precedence[tok]);
- if (b.get(b.size() - 1) != GET)
- throw new ParserException("prefixed increment/decrement can only be performed on a valid assignment target");
+ if (b.get(b.size() - 1) != GET)
+ throw pe("prefixed increment/decrement can only be performed on a valid assignment target");
b.set(b.size() - 1, tok, new Boolean(true));
break;
}
if (peekToken() != RC)
while(true) {
if (peekToken() != NAME && peekToken() != STRING)
- throw new ParserException("expected NAME or STRING");
+ throw pe("expected NAME or STRING");
getToken();
b.add(parserLine, LITERAL, string); // grab the key
consume(COLON);
break;
}
case NAME: {
- b.add(parserLine, TOPSCOPE);
- b.add(parserLine, LITERAL, string);
- continueExprAfterAssignable(b);
- break;
+ b.add(parserLine, TOPSCOPE);
+ b.add(parserLine, LITERAL, string);
+ continueExprAfterAssignable(b);
+ break;
}
case FUNCTION: {
consume(LP);
break;
}
- default: throw new ParserException("expected expression, found " + codeToString[tok] + ", which cannot start an expression");
+ default: throw pe("expected expression, found " + codeToString[tok] + ", which cannot start an expression");
}
// attempt to continue the expression
* decreases the stack depth by exactly one element.
*/
private void continueExprAfterAssignable(CompiledFunctionImpl b) throws IOException {
- int saveParserLine = parserLine;
- _continueExprAfterAssignable(b);
- parserLine = saveParserLine;
+ int saveParserLine = parserLine;
+ _continueExprAfterAssignable(b);
+ parserLine = saveParserLine;
}
private void _continueExprAfterAssignable(CompiledFunctionImpl b) throws IOException {
if (b == null) throw new Error("got null b; this should never happen");
int tok = getToken();
- switch(tok) {
+ switch(tok) {
case ASSIGN_BITOR: case ASSIGN_BITXOR: case ASSIGN_BITAND: case ASSIGN_LSH: case ASSIGN_RSH: case ASSIGN_URSH:
case ASSIGN_ADD: case ASSIGN_SUB: case ASSIGN_MUL: case ASSIGN_DIV: case ASSIGN_MOD: {
- b.add(parserLine, GET_PRESERVE);
+ b.add(parserLine, GET_PRESERVE);
startExpr(b, -1);
b.add(parserLine, tok - 1);
b.add(parserLine, PUT);
break;
}
case INC: case DEC: { // postfix
- b.add(parserLine, GET_PRESERVE);
- b.add(parserLine, LITERAL, new Integer(1));
- b.add(parserLine, tok == INC ? ADD : SUB);
- b.add(parserLine, PUT);
- b.add(parserLine, SWAP);
- b.add(parserLine, POP);
- b.add(parserLine, LITERAL, new Integer(1));
- b.add(parserLine, tok == INC ? SUB : ADD);
- break;
- }
- case ASSIGN: {
+ b.add(parserLine, GET_PRESERVE);
+ b.add(parserLine, LITERAL, new Integer(1));
+ b.add(parserLine, tok == INC ? ADD : SUB);
+ b.add(parserLine, PUT);
+ b.add(parserLine, SWAP);
+ b.add(parserLine, POP);
+ b.add(parserLine, LITERAL, new Integer(1));
+ b.add(parserLine, tok == INC ? SUB : ADD);
+ break;
+ }
+ case ASSIGN: {
startExpr(b, -1);
- b.add(parserLine, PUT);
- b.add(parserLine, SWAP);
- b.add(parserLine, POP);
- break;
- }
- default: {
- pushBackToken();
- b.add(parserLine, GET);
- return;
- }
- }
+ b.add(parserLine, PUT);
+ b.add(parserLine, SWAP);
+ b.add(parserLine, POP);
+ break;
+ }
+ default: {
+ pushBackToken();
+ b.add(parserLine, GET);
+ return;
+ }
+ }
}
* depth.
*/
private void continueExpr(CompiledFunctionImpl b, int minPrecedence) throws IOException {
- int saveParserLine = parserLine;
- _continueExpr(b, minPrecedence);
- parserLine = saveParserLine;
+ int saveParserLine = parserLine;
+ _continueExpr(b, minPrecedence);
+ parserLine = saveParserLine;
}
private void _continueExpr(CompiledFunctionImpl b, int minPrecedence) throws IOException {
if (b == null) throw new Error("got null b; this should never happen");
startExpr(b, precedence[tok]); // otherwise check the second value
b.add(parserLine, JMP, new Integer(2)); // leave the second value on the stack and jump to the end
b.add(parserLine, LITERAL, tok == AND ?
- new Boolean(false) : new Boolean(true)); // target of the short-circuit jump is here
+ new Boolean(false) : new Boolean(true)); // target of the short-circuit jump is here
b.set(size - 1, new Integer(b.size() - size)); // write the target of the short-circuit jump
break;
}
case DOT: {
consume(NAME);
- b.add(parserLine, LITERAL, string);
- continueExprAfterAssignable(b);
- break;
+ b.add(parserLine, LITERAL, string);
+ continueExprAfterAssignable(b);
+ break;
}
case LB: { // subscripting (not array constructor)
startExpr(b, -1);
consume(RB);
- continueExprAfterAssignable(b);
- break;
+ continueExprAfterAssignable(b);
+ break;
}
case HOOK: {
b.add(parserLine, JF, new Integer(0)); // jump to the if-false expression
/** Parse a block of statements which must be surrounded by LC..RC. */
void parseBlock(CompiledFunctionImpl b) throws IOException { parseBlock(b, null); }
void parseBlock(CompiledFunctionImpl b, String label) throws IOException {
- int saveParserLine = parserLine;
- _parseBlock(b, label);
- parserLine = saveParserLine;
+ int saveParserLine = parserLine;
+ _parseBlock(b, label);
+ parserLine = saveParserLine;
}
void _parseBlock(CompiledFunctionImpl b, String label) throws IOException {
if (peekToken() == -1) return;
/** Parse a single statement, consuming the RC or SEMI which terminates it. */
void parseStatement(CompiledFunctionImpl b, String label) throws IOException {
- int saveParserLine = parserLine;
- _parseStatement(b, label);
- parserLine = saveParserLine;
+ int saveParserLine = parserLine;
+ _parseStatement(b, label);
+ parserLine = saveParserLine;
}
void _parseStatement(CompiledFunctionImpl b, String label) throws IOException {
int tok = peekToken();
consume(COMMA);
}
b.add(parserLine, POP); // pop off the topscope
- if ((mostRecentlyReadToken != RC || peekToken() == SEMI) && peekToken() != -1) consume(SEMI);
+ if ((mostRecentlyReadToken != RC || peekToken() == SEMI) && peekToken() != -1 && mostRecentlyReadToken != SEMI) consume(SEMI);
break;
}
case IF: {
if (label != null) b.add(parserLine, LABEL, label);
b.add(parserLine, LOOP);
int size = b.size();
- b.add(parserLine, POP); // discard the first-iteration indicator
+ b.add(parserLine, POP); // discard the first-iteration indicator
startExpr(b, -1);
b.add(parserLine, JT, new Integer(2)); // if the while() clause is true, jump over the BREAK
b.add(parserLine, BREAK);
b.add(parserLine, BREAK); // break out of the loop if we 'fall through'
break;
} else {
- throw new ParserException("expected CASE, DEFAULT, or RC; got " + codeToString[peekToken()]);
+ throw pe("expected CASE, DEFAULT, or RC; got " + codeToString[peekToken()]);
}
b.set(size0 - 1, new Integer(b.size() - size0 + 1)); // end of the loop
break;
pushBackToken(NAME, possiblyTheLabel);
startExpr(b, -1);
b.add(parserLine, POP);
- if ((mostRecentlyReadToken != RC || peekToken() == SEMI) && peekToken() != -1) consume(SEMI);
+ if ((mostRecentlyReadToken != RC || peekToken() == SEMI) && peekToken() != -1 && mostRecentlyReadToken != SEMI) consume(SEMI);
break;
}
}
case LC: { // blocks are statements too
pushBackToken();
- b.add(parserLine, NEWSCOPE);
+ b.add(parserLine, NEWSCOPE);
parseBlock(b, label);
- b.add(parserLine, OLDSCOPE);
+ b.add(parserLine, OLDSCOPE);
break;
}
pushBackToken();
startExpr(b, -1);
b.add(parserLine, POP);
- if ((mostRecentlyReadToken != RC || peekToken() == SEMI) && peekToken() != -1) consume(SEMI);
+ if ((mostRecentlyReadToken != RC || peekToken() == SEMI) && peekToken() != -1 && mostRecentlyReadToken != SEMI) consume(SEMI);
break;
}
}
// ParserException //////////////////////////////////////////////////////////////////////
-
- private class ParserException extends IOException { public ParserException(String s) { super(sourceName + ":" + parserLine + " " + s); } }
+ private IOException pe(String s) { return new IOException(sourceName + ":" + parserLine + " " + s); }
}
projects / org.ibex.core.git / blobdiff