std::unique_ptr<ExpressionSeriesAST> ExpressionSeriesAST::generate(Lexer &l) {
std::vector<std::unique_ptr<ExpressionAST>> expressions;
//a statement series ends with a curly bracket
while (1) {
//if there is a close curly bracket, stop the series
if (l.curToken() == Token::Char_closeCurlyBracket) {
return llvm::make_unique<ExpressionSeriesAST>(l, std::move(expressions));
}
//parse an expression
auto expr = ExpressionAST::generate(l);
if (expr != nullptr) {
if (l.curToken() == Token::Char_semicolon) {
//generate an expressionkiller
expressions.push_back(llvm::make_unique<ExpressionKillerAST>(l, std::move(expr)));
//eat the semicolon and continue
l.nextToken();
} else if (l.curToken() == Token::Char_closeCurlyBracket) {
expressions.push_back(std::move(expr));
} else {
COMPILE_GENERATE_AND_RETURN_ERROR(l, "Expected ';' or '}' in expressionseries.");
}
}
}
}
std::unique_ptr<FunctionPrototypeAST> FunctionPrototypeAST::generate(Lexer &l) {
//eat the function token
l.nextToken();
//get the name of the function and eat it
COMPILE_ASSERT(l.curToken() == Token::Identifier, "Expected identifier in function prototype.");
std::string name = l.value.string;
l.nextToken();
std::vector<std::string> args;
std::vector<std::string> types;
std::string type;
//make sure we are now in brackets
COMPILE_ASSERT(l.curToken() == Token::Char_openRoundBracket, "Expected '(' after function identifier.");
l.nextToken();
//keep fetching pairs of tokens until we have no more commas
while (l.curToken() != Token::Char_closeRoundBracket) {
//eat the type
COMPILE_ASSERT(l.curToken() == Token::Identifier || l.curToken() == Token::Type, "Parameter should start with a type.");
types.push_back(l.value.string);
l.nextToken();
//and the name
COMPILE_ASSERT(l.curToken() == Token::Identifier, "Parameter should end with an identifier.");
args.push_back(l.value.string);
l.nextToken();
//if we do not have a ',' break
if (l.curToken() != Token::Char_comma)
break;
l.nextToken();
}
//brackets should be closed
COMPILE_ASSERT(l.curToken() == Token::Char_closeRoundBracket, "Expected ')' after function argument list.");
l.nextToken();
//if the next token is a ->, we get the type
if (l.curToken() == Token::Char_arrow) {
l.nextToken();
COMPILE_ASSERT(l.curToken() == Token::Identifier || l.curToken() == Token::Type, "Function return type is not a type.");
type = l.value.string;
l.nextToken();
} else {
type = "void";
}
return llvm::make_unique<FunctionPrototypeAST>(l, type, name, std::move(args), std::move(types));
}
