Use the BRE construct \{1,\} for one or more consecutive matches

[lexprfuncall]

This removes duplication introduced by my earlier commit that eliminating the use of the non-standard "+" from BREs in the configure script.

[guangli-dai]

Does the usage of \{1,\} introduce any compatibility concern here? The CI seems to indicate all relatively new OSes (FreeBSD, windows, mac and of course Linux) are all fine with it. But just want to confirm if there are any systems not compatible with this in your mind?

[lexprfuncall]

Does the usage of \{1,\} introduce any compatibility concern here? The CI seems to indicate all relatively new OSes (FreeBSD, windows, mac and of course Linux) are all fine with it. But just want to confirm if there are any systems not compatible with this in your mind?

\{1,\} is part of the standard grammar for POSIX BRE so everyone should be fine with it. To validate this change, I tested it on a real grep from UNIX sources (which have no GNU extensions) and it works just fine.

I should have used this idiom to begin with as the replacement for \+ but, at the time, I forgot you could leave out the second number in a bracketed expression. Personally, I mostly use { } in a form like {N} or {N,M} just not {N,}.