On 8/24/15, Joseph Wright <[log in to unmask]> wrote: > On 25/08/2015 01:33, aparsloe wrote: >> It has taken me a while to get to grips with \tl_set_rescan:Nnn <tl var> >> {setup} {tokens}, not least the fact that *omission* from the setup >> means "revert to usual catcode". I think this is worth documenting in >> interface3.pdf, since it seems not unreasonable (at least it did to me) >> to suppose that if one has explicitly changed a catcode using >> \tl_set_rescan:Nnn, only a similarly explicit change would revert the >> catcode to its usual value. In particular it would be helpful to >> document the fact that using an empty setup { } reverts everything to >> usual values. >> >> Andrew > > I see what you mean: I'll add a note that any chars not set up > explicitly will have the *current* catcode applied. (That's not quite > the same as saying the 'usual' value.) > > Worth noting perhaps that rescanning tokens is in general a bit tricky > to use safely. (Certainly if possible I find other ways of solving > problems.) (Off-list to avoid noise.) If you do change the doc, please include a comment along those lines (that rescanning is typically not the best approach). Bruno