Perl::Critic::Policy::ValuesAndExpressions::NotWithCompare - logical not used with compare

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perl v5.32.1                                       2021-02-28             Perl::Critic::P...:NotWithCompare(3pm)

       This policy is part of the "Perl::Critic::Pulp" add-on.  It picks up some cases of logical not "!" used
       with a comparison, like

           ! $x =~ /^[123]/  # bad
           ! $x + $y >= $z   # bad

       In each case precedence means Perl parses this as "(!$x)", like

           (! $x) =~ /^[123]/
           (! $x) + $y >= $z

       rather than a negated comparison.  Usually this is a mistake, so this policy is under the "bugs" theme
       (see "POLICY THEMES" in Perl::Critic).

       As a special case, "!" on both sides of "==" or "!=" is allowed, since it's quite a good way to compare
       booleans.

           !$x == !$y   # ok
           !$x != !$y   # ok

http://user42.tuxfamily.org/perl-critic-pulp/index.html

       User functions called without parentheses are assumed to be usual varargs style.  But a prototype may
       mean that's not the case, letting a bad "!"-with-compare expression to go undetected.

           ! userfunc $x == 123   # indeterminate
           # without prototype would be ok:   ! (userfunc ($x==123))
           # with ($) prototype would be bad: (! userfunc($x)) == 123

       Perl builtins with no args, and constant subs created with "use constant" or "sub FOO () {...}" in the
       file under test are recognised.  Hopefully anything else too weird is rare.

           ! time == 1   # bad

           use constant FIVE => 5;
           ! FIVE < 1    # bad

           sub name () { "foo" }
           ! name =~ /bar/    # bad

       Perl::Critic::Policy::ValuesAndExpressions::NotWithCompare - logical not used with compare

       Perl::Critic::Pulp, Perl::Critic