noble (3) Perl::Critic::Policy::Documentation::ProhibitUnbalancedParens.3pm.gz
NAME
Perl::Critic::Policy::Documentation::ProhibitUnbalancedParens - don't leave an open bracket or paren
DESCRIPTION
This policy is part of the "Perl::Critic::Pulp" add-on. It reports unbalanced or mismatched parentheses,
brackets and braces in POD text paragraphs,
Blah blah (and something. # bad
Blah blah ( [ ). # bad
Blah blah brace }. # bad
This is only cosmetic and normally only a minor irritant to readability so this policy is low severity
and under the "cosmetic" theme (see "POLICY THEMES" in Perl::Critic).
Text and command paragraphs are checked, but verbatim paragraphs can have anything. There are some
exceptions to paren balancing. The intention is to be forgiving of common or reasonable constructs.
Currently this means,
• Anything in "C<>" code markup is ignored
In code C<anything [ is allowed>. # ok
Perhaps this will change, though there'd have to be extra exceptions in "C<>", such as various
backslashing.
Sometimes a prematurely ending "C<>" may look like an unbalanced paren, for example
Call C<foo(key=>value)> ... # bad
This is bad because the "C<>" ends at the "=>", leaving "value)" unbalanced plain text. This is an
easy mistake to make. (The author's "perl-pod-gt.el" can show warning face on this in Emacs.)
• Quoted "(" is taken to be describing the char and is not an open or close.
Any of "(" or '[' or "[{]". # ok
This only applies to quoted parens alone (one or more), not larger quoted text.
• Item parens
a) the first thing, or b) the second thing # ok
1) one, 2) two # ok
Exactly how much is recognised as an "a)" etc is not quite settled. In the current code a "1.5)" is
recognised at the start of a paragraph, but in the middle only "1)" style.
• Smiley faces are an "optional" close,
(Some thing :-). # ok
Bare smiley :). # ok
(Or smile :-) and also close.) # ok
• Sad smiley faces are not an opening paren,
:( :-(. # ok
• Perl variables $( and $[ are not opening parens,
Default is group $( blah blah. # ok
${ brace is still an open and expected to have a matching close, because it's likely to be a deref or
delimiter,
Deref with ${foo()} etc etc.
Variables or expressions like this will often be in "C<>" markup and skipped for that reason instead,
as described above.
• $) and $] are optional closes, since they might be Perl variables to skip, or might be "$" at the end
of a parens,
blah blah (which in TeX is $1\cdot2$).
Perhaps the conditions for these will be restricted a bit, though again "C<>" markup around sample
code like this will be usual.
• "L<display|link>" links are processed as the "display" text part. The link target (POD document name
and section) can have anything.
"=begin :foo" ... "=end :foo" sections with a format name ":foo" starting with a ":" are POD markup and
are processed accordingly. Other "=begin" sections are skipped.
Unrecognised Forms
A mathematical half-open range like the following is not recognised.
[1,2) # bad, currently
Perhaps just numbers like this would be unambiguous, but if it's an expression then it's hard to
distinguish a parens typo from some mathematics. The suggestion for now is an "=for" per below to flag
it as an exception. Another way would be to write 1 <= X < 2, which might be clearer to mathematically
unsophisticated readers.
Parens spanning multiple paragraphs are not recognised,
(This is some # bad
thing.) # bad
Hopefully this is uncommon, and probably better style not to be parenthetical about something so big that
it runs to multiple paragraphs or has a verbatim block in the middle etc.
Disabling
If an unbalanced paren is intended you can add an "=for" to tell "ProhibitUnbalancedParens" to allow it.
=for ProhibitUnbalancedParens allow next
Something ( deliberately unclosed.
Or with a count of paragraphs to ignore,
=for ProhibitUnbalancedParens allow next 2
First deliberate [ unclosed.
Second (.
The usual no critic
## no critic (ProhibitUnbalancedParens)
works too as a whole-file disable, but the annotation must be before any "__END__" token, and if the POD
is after the "__END__" then "Perl::Critic" 1.112 up is required. Individual "=for" has the advantage of
being with an exception.
As always if you don't care about this at all you can disable "ProhibitUnbalancedParens" completely from
your .perlcriticrc in the usual way (see "CONFIGURATION" in Perl::Critic),
[-Documentation::ProhibitUnbalancedParens]
SEE ALSO
Perl::Critic::Pulp, Perl::Critic
<http://user42.tuxfamily.org/perl-pod-gt/index.html>
HOME PAGE
http://user42.tuxfamily.org/perl-critic-pulp/index.html
COPYRIGHT
Copyright 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2019, 2021 Kevin Ryde
Perl-Critic-Pulp is free software; you can redistribute it and/or modify it under the terms of the GNU
General Public License as published by the Free Software Foundation; either version 3, or (at your
option) any later version.
Perl-Critic-Pulp is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
Public License for more details.
You should have received a copy of the GNU General Public License along with Perl-Critic-Pulp. If not,
see <http://www.gnu.org/licenses/>.
perl v5.32.1 Perl::Critic::Policy::Documentation::ProhibitUnbalancedParens(3pm)