bool PPUnaryExpression(PPScanner scan)
{
bool not = false;
PPToken ppt = scan.peek();
while (ppt.getKind() == PPToken.eNot) {
scan.next();
not = !not;
ppt = scan.peek();
}
return not ^ PPPrimaryExpression(scan);
}
bool PPPrimaryExpression(PPScanner scan)
{
bool e = false;
PPToken ppt = scan.next();
if (ppt.getKind() == PPToken.eTrue) {
e = true;
} else if (ppt.getKind() == PPToken.eFalse) {
e = false;
} else if (ppt.getKind() == PPToken.eLPar) {
e = PPOrExpression(scan);
ppt = scan.next();
if (ppt.getKind() != PPToken.eRPar) {
Error("Corrupt preprocessor directive (')' expected), found: " + ppt.toString());
}
} else if (ppt.getKind() == PPToken.eIdent) {
e = ccs.Contains(ppt.getValue());
} else {
Error("Corrupt preprocessor directive, unknown start of PPPrimaryExpression: " + ppt.toString());
}
return e;
}
// preprocessor expression parser start
bool PPOrExpression(PPScanner scan)
{
bool e1, e2;
e1 = PPAndExpression(scan);
while (scan.peek().getKind() == PPToken.eOr) {
scan.next();
e2 = PPAndExpression(scan);
e1 = e1 || e2;
}
return e1;
}
bool PPEqualityExpression(PPScanner scan)
{
bool e1, e2;
e1 = PPUnaryExpression(scan);
int tk = scan.peek().getKind();
while (tk == PPToken.eEQ || tk == PPToken.eNE) {
scan.next();
e2 = PPUnaryExpression(scan);
if (tk == PPToken.eEQ) {
e1 = e1 == e2;
} else {
// tk == PPToken.eNE
e1 = e1 != e2;
}
tk = scan.peek().getKind();
}
return e1;
}
bool PPAndExpression(PPScanner scan)
{
bool e1, e2;
e1 = PPEqualityExpression(scan);
while (scan.peek().getKind() == PPToken.eAnd) {
scan.next();
e2 = PPEqualityExpression(scan);
e1 = e1 && e2;
}
return e1;
}
// preprocessor expression parser end
// ccs.Contains(RemPPDirective(symbol))
bool IsCCS(string symbol)
{
// skip "#" "if", "#" "elif"
PPScanner scan = new PPScanner(symbol);
PPToken ppt = scan.next();
if (ppt.getKind() != PPToken.eHash) {
Error("Corrupt preprocessor directive, # expected, but found: " + ppt.toString());
}
ppt = scan.next();
if (ppt.getKind() != PPToken.eIdent) {
Error("Corrupt preprocessor directive, identifier expected, but found: " + ppt.toString());
}
return PPOrExpression(scan);
}