private Declaration ParseFuncDeclaration()
{
Token start = Match(TokenKind.Keyword_Func);
string identifier = Match(TokenKind.Identifier).Text;
// parse parameter list
Match(TokenKind.LeftParenthesis);
List <ParameterDeclaration> parameters = new List <ParameterDeclaration>();
while (_lookahead.Kind != TokenKind.RightParenthesis)
{
Token name = Match(TokenKind.Identifier);
Match(TokenKind.Colon);
AST.Type type = ParseType();
parameters.Add(new ParameterDeclaration(name.Position, name.Text, type));
if (_lookahead.Kind != TokenKind.Comma)
{
break;
}
Match(TokenKind.Comma);
}
Match(TokenKind.RightParenthesis);
// parse return type specification
Match(TokenKind.Colon);
AST.Type returnType = ParseType();
Match(TokenKind.Tilde);
Expression body = ParseExpression();
return(new FunctionDeclaration(start.Position, identifier, returnType, parameters.ToArray(), body));
}
private Declaration ParseVariableDeclaration()
{
Token start = Match(TokenKind.Keyword_Var);
Token name = Match(TokenKind.Identifier);
Match(TokenKind.Colon);
AST.Type type = ParseType();
return(new VariableDeclaration(start.Position, name.Text, type));
}