From tim_meadowcroft@westlb.co.uk

The perlre.pod page doesn't explain a certain behaviour in character
classes, namely that "]" as the first character in a character class is
taken as a literal "]", not as the terminator of the class.

Perldiag alludes to this,

unmatched [] in regexp

  (F) The brackets around a character class must match.
  If you wish to include a closing bracket in a character
  class, backslash it or put it first. See the perlre manpage.

but I can't find anywhere else in the standard docs that explains this (nor
is it in J Friedl's "Mastering Regular Expressions", but I guess I'll mail
him seperately).

As such, can I suggest the addtion of a phrase such as

  If you want "]" itself to be a member of a class,
  put it at the start of the list (after a possible "^")
  or escape it with a backslash.

to the paragraph about character classes in the perlre.pod file.

I would suggest that the paragraph about character classes (under head2
"Version 8 Regular Expressions")

  You can specify a character class, by enclosing a list of characters
  in C<[]>, which will match any one character from the list. If the
  first character after the "[" is "^", the class matches any character not
  in the list. Within a list, the "-" character is used to specify a
  range, so that C<a-z> represents all characters between "a" and "z",
  inclusive. If you want "-" itself to be a member of a class, put it
  at the start or end of the list, or escape it with a backslash. (The
  following all specify the same class of three characters​: C<[-az]>,
  C<[az-]>, and C<[a\-z]>. All are different from C<[a-z]>, which
  specifies a class containing twenty-six characters.)

be changed as follows... (this is line 729 in my distrib)

<< in the list. Within a list, the "-" character is used to specify a

in the list. If you want "]" itself to be a member of a class,
put it at the start of the list (after a possible "^") or escape it
with
a backslash. Within a list, the "-" character is used to specify a

Regards

Tim Meadowcroft

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