in reply to Problem with perlcritic when using Moose object

Edited (again): As haukex points out in his reply, I've apparently just been paranoiac without a good reason. There's nothing wrong with an unquoted shift within braces, the following advice can safely be scratched.

Instead of if($hash->{shift}) { $Person->shift( $hash->{shift} ); } use: 
if($hash->{'shift'})     { $Person->shift( $hash->{'shift'} );  }

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The Perl parser could confuse the bareword shift in the braces with its core function shift instead of converting it to a string. (edited because I tested the stuff and found out that it does not confuse it right now).

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Re^2: Problem with perlcritic when using Moose object
by haukex (Archbishop) on Oct 05, 2018 at 15:07 UTC
    The Perl parser could confuse the bareword shift in the braces with its core function shift instead of converting it to a string.

    I'm pretty sure that Perl will always take $hash{shift} to mean the hash key "shift", although adding any other characters will change that ($hash{+shift}, $hash{shift()}, etc.) See also.

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      I'm pretty sure that Perl will always take $hash{shift} to mean the hash key "shift", although adding any other characters will change that ($hash{+shift}, $hash{shift()}, etc.)

      I guess you're right. I've posted from memory because I thought that I had been bitten by something like that in the past. However, I failed to find any evidence, nor could I construct any test supporting my case. Quite on the contrary, I found that some other characters won't even prevent stringification, as is demonstrated by Tk's habit of having $hashref->{-option} reliably interpreted as $hashref->{'-option'}.

      Thanks for the correction!

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        $hashref->{-option} reliably interpreted as $hashref->{'-option'}

        Interestingly, the former is actually interpreted as an expression (note the "negate" below), but the because of the properties of unary -, -bareword is the same as "-bareword". As of v5.26, "Bareword constant strings are now permitted to take part in constant folding."

        $ perlbrew exec --with 5.24.4,5.26.2 perl -MO=Concise -wMstrict -e 'my
+ %hash; print $hash{-foo}'

perl-5.24.4
==========
b  <@> leave[1 ref] vKP/REFC ->(end)
1     <0> enter ->2
2     <;> nextstate(main 2 -e:1) v:*,&,{,x*,x&,x$,$ ->3
3     <0> padhv[%hash:2,3] vM/LVINTRO ->4
4     <;> nextstate(main 3 -e:1) v:*,&,{,x*,x&,x$,$ ->5
a     <@> print vK ->b
5        <0> pushmark s ->6
9        <2> helem sK/2 ->a
6           <0> padhv[%hash:2,3] sR ->7
8           <1> negate[t2] sK/1 ->9
7              <$> const(PV "foo") s/BARE ->8
-e syntax OK


perl-5.26.2
==========
8  <@> leave[1 ref] vKP/REFC ->(end)
1     <0> enter ->2
2     <;> nextstate(main 2 -e:1) v:*,&,{,x*,x&,x$,$ ->3
3     <0> padhv[%hash:2,3] vM/LVINTRO ->4
4     <;> nextstate(main 3 -e:1) v:*,&,{,x*,x&,x$,$ ->5
7     <@> print vK ->8
5        <0> pushmark s ->6
-        <1> ex-helem sK/2 ->7
6           <+> multideref($hash{"-foo"}) sK ->7
-              <0> ex-padhv sR ->6
-e syntax OK

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Re^2: Problem with perlcritic when using Moose object
by Anonymous Monk on Oct 05, 2018 at 20:04 UTC
    Nope. A false positive is a false positive. Thats a poorly written critic policy
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