private static AstFor ParseForIn(TokenStream tks)
{
var si = tks.SourceInfo;
tks.Expect(TokenType.For);
var ident = tks.Expect(TokenType.Ident).StringValue;
tks.Expect(TokenType.In);
var @from = ParseExpression(tks);
tks.Expect(TokenType.DotDot);
var to = ParseExpression(tks);
var opTk = tks.Accept(TokenType.Plus, TokenType.Minus);
var updateOp = opTk?.Type ?? TokenType.Plus;
tks.Expect(TokenType.LCurBracket);
var body = ParseBody(tks);
tks.Expect(TokenType.RCurBracket);
var pre = new AstDeclaration(si, ident, null, @from);
var condOp = (updateOp == TokenType.Plus)
? TokenType.LessThanEquals
: TokenType.GreaterThanEquals;
var itrId = new AstIdent(si, ident);
var cond = new AstBinaryOp(si, itrId, condOp, to);
var update_ = new AstBinaryOp(si, itrId, updateOp, new AstNumber(si, 1));
var update = new AstAssign(si, itrId, update_);
return(new AstFor(si, new List <AstNode> {
pre
}, cond, new List <AstExpression> {
update
}, body));
}
public void AddMember(AstDeclaration member)
{
_members.Add(member.Name, member);
}
