WhileExprAST *Parser::handleWhile() {
ExprAST *expr, *whileBlock = nullptr;
int whileLine = currentToken.line;
getNextToken();
if (currentToken.type != TOK_OPARENTHESES) {
return ErrorW("Expecting '(' for 'while' loop", whileLine);
}
getNextToken();
expr = handleExpression();
if (currentToken.type != TOK_CPARENTHESES) {
return ErrorW("Expecting ')' for 'while' loop", whileLine);
}
getNextToken();
if(currentToken.type!=TOK_OBRACES) {
return ErrorW("Expecting '{' for 'while' loop", whileLine);
}
getNextToken();
whileBlock = handleExpression();
return new WhileExprAST(expr,whileBlock);
}
ExprAST *Parser::handleIdentifierExpression() {
std::string identifier = currentToken.value;
getNextToken();
if(currentToken.type != TOK_OPARENTHESES)
{
auto var = _variables[identifier];
return new IdentifierExprAST(var);
}
getNextToken();
std::vector<ExprAST *> Args;
if(currentToken.type!=TOK_CPARENTHESES){
while(1){
if(auto Arg = handleExpression())
Args.push_back(Arg);
else
return nullptr;
if(currentToken.type==TOK_CPARENTHESES)
break;
getNextToken();
}
}
return new CallExprAST(identifier);
}
ExprAST *Parser::handleReturn() {
if(currentToken.type == TOK_RETURN)
getNextToken();
return new ReturnExprAST(handleExpression());
}
ExprAST *Parser::handlePrintf() {
getNextToken();
if(currentToken.type==TOK_OPARENTHESES){
getNextToken();
return new PrintExprAST(handleExpression());
}
return nullptr;
}
IfExprAST *Parser::handleIf() {
ExprAST *Cond, *Then, *Else = nullptr;
int ifLine = currentToken.line;
getNextToken();
if(currentToken.type!=TOK_OPARENTHESES){
printf("Exp (");
parsed = false;
}
getNextToken();
Cond = handleExpression();
if(currentToken.type!=TOK_CPARENTHESES){
return ErrorI("Expecting ) for 'if' statement", ifLine);
}
getNextToken();
if(currentToken.type!=TOK_OBRACES) {
return ErrorI("Expecting { for If statement", ifLine);
}
getNextToken();
Then = handleExpression();
getNextToken();
if(currentToken.type==TOK_ELSE) {
getNextToken();
if (currentToken.type == TOK_OBRACES) {
getNextToken();
Else = handleExpression();
}
getNextToken();
}
return new IfExprAST(Cond,Then,Else);
}
ExprAST *Parser::handleParenthesesExpression() {
ExprAST *expr = nullptr;
getNextToken();
expr = handleExpression();
if(currentToken.type!=TOK_CPARENTHESES){
return Error("missing )", currentToken.line);
}
getNextToken();
return expr;
}
void Parser::parse() {
getNextToken();
while(currentToken.type != TOK_EOF){
switch (currentToken.type){
case TOK_CBRACES:
getNextToken();
break;
default:
_expressions.push_back(handleExpression());
getNextToken();
break;
}
}
}
FunctionAST *Parser::handleFunction(std::string identifier, std::string type)
{
getNextToken();
PrototypeAST *prototype = handlePrototype(identifier,type);
ExprAST *body = nullptr;
getNextToken();
body = handleExpression();
return new FunctionAST(prototype, body);
}
void handleArray(string line){
if(contains(line, "<callArray>")){
if (contains(getNextLine(), "<identifier>")) {
string id = getCurrLine();
handleExpression(getNextLine());//looks inside [...]
handleIdentifier(id);//pushes array name on stack
writeArithmetic("+");//offset array
//writePop("pointer", 1); //set point to correct place in memory
// writePush("that", 0); //place array[offset] on stack
while ( !contains(getCurrLine(), "</callArray>")) {
incFilePtr();
}
}else{
error("expected to get array name <identifier> at this point");
}
}else{
error("expected callArray");
}
}