Hi,
I'm working on finalizing an extension to spirit/qi in which I need to
extract an attribute from a fusion sequence in a parser context.
The problem I'm facing is that this parser attribute can be an unused
type or a valid fusion sequence.
Just to illustrate my problem:
template
struct parser_dispachter
{
template <typename Index>
void parse(Index &idx, Attribute &attr)
{
fusion::at_cIndex::value(Elements).parse(fusion::at_cIndex::value(attr));
}
};
I actually have two cases:
1. Attribute = unused_type -> at_c replacement should return unused
2. Attribute = fusion sequence -> at_c replacement should return the
corresponding attribute reference.
What would be the best solution to extract the give attribute ?
Regards,
Thomas Bernard
