internal override bool Parse(ParseContext context, ParseRule rule, out Token result)
{
OrderedChoiceMemento state;
if (context.Recovering)
state = (OrderedChoiceMemento)context.Recover();
else
state = new OrderedChoiceMemento(context);
context.BeginExpression(state);
// Parse each subexpression until the first match
for (; state.index < ExpressionCount; ++state.index) {
var expr = Expression(state.index);
Token t;
// Parsing succeeded on a subexpression - return the result
if (expr.Parse(context, rule, out t)) {
context.EndExpression();
result = t;
return true;
}
context.Offset = state.offset;
}
context.EndExpression();
return context.Reject(rule, this, out result);
}
private OrderedChoiceMemento(OrderedChoiceMemento m)
{
this.offset = m.offset;
this.index = m.index;
}
