Re: succinct awk code to check for paired parantheses?

[Wolfgang Laun]

Gawk Regex experts might like to comment on my statement re escaping (not).

On Wed, 24 Mar 2021 at 22:35, Manuel Collado <mcollado2011@gmail.com> wrote:

> function paired(text) {
>      while (gsub(/\([^()[\]{}]*\)/,"",text) \
>          +  gsub(/\[[^()[\]{}]*\]/,"",text) \
>          +  gsub(/\{[^()[\]{}]*\}/,"",text) \
>      ) {}  # just replace pairs
>      return text !~ /[()[\]{}]/
> }
>

I had been thinking along similar lines. As I always try to reduce the use
of escaping, I came up with:

function isBalanced(s){
   gsub( /[^][)(}{]+/, "", s );       # only ']' is tricky in [...]
   while( gsub( /\(\)|{}|\[]/, "", s ) );   # an empty {} is not "magic",
and neither are unbalanced ']' and ')'
   return length(s) == 0;
}

Regex documentations (across languages) hardly ever mention that my
parsimonious use of escaping is according to the book. The rule would be
something like "if it cannot be parsed as a correct construct it shall be
used as a literal character." (I think of it as the "un-printed small
print".)

Thank you
Wolfgang