private TexlNode ParseParenExpr()
{
Contracts.Assert(_curs.TidCur == TokKind.ParenOpen);
var open = _curs.TokMove();
var before = ParseTrivia();
// SingleExpr here means we don't want chains, but individual expressions.
TexlNode node = ParseExpr(Precedence.SingleExpr);
var after = ParseTrivia();
var close = TokEat(TokKind.ParenClose);
var sources = new List <ITexlSource>
{
new TokenSource(open),
before,
new SpreadSource(node.SourceList.Sources),
after
};
if (close != null)
{
sources.Add(new TokenSource(close));
}
node.Parser_SetSourceList(new SourceList(new SpreadSource(sources)));
return(node);
}