Is there a way to process only on success and peek on error?

[EmmanuelMess]

I want to write code that "autobacktracks" whenever an error occurs, it seems that

static constexpr auto rule = [] {
    auto ws = dsl::whitespace(dsl::ascii::space);
    auto condition = dsl::peek( rule using ws );
    
    return condition >> rule not using ws;
}();

is the only way. But this makes me write the same rule twice, but for the first one I have to use whitespace.

If I don't use this syntax I run the risk of a series of tokens being read by the wrong production and breaking unexpectedly without recovery.

(Also clangd seems annoyed that ws is two letters)

[foonathan]

This isn't how lexy is meant to be used, so there is no easy way to get it.