github.com/benhoyt/goawk@v1.8.1/testdata/gawk/regrange.ok (about)

     1  "." ~ /[--\/]/ --> 1
     2  "a" ~ /[]-c]/ --> 1
     3  "c" ~ /[[a-d]/ --> 1
     4  "\" ~ /[\[-\]]/ --> 1
     5  invalid regex "[a-[.e.]]": error parsing regexp: invalid character class range: `a-[`