Re^8: Perl list items

To clarify @$c[0] means the same as @{$c}[0] meaning dereference $c, take array slice

 
$ perl -e " use Data::Dump; my $c = [qw/ a b c/]; dd @$c[1,2]; "
("b", "c")
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While References quick reference lists this item explicitly (item 2), its somewhat documented in perlreftut/perlref but its not recommended

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Re^9: Perl list items by AnomalousMonk (Archbishop) on Jul 10, 2012 at 09:13 UTC
To clarify @$c[0] means the same as @{$c}[0] meaning dereference $c, take array slice Well... I'm not sure it's that much more clear. After all, "I know what I mean, ..." I'm still puzzled by the absence of a "... better written as ..." warning. Maybe the usage is just too far off the beaten track for warnings to stumble over. `>perl -wMstrict -le "my @c = ('foo'); print @c[0]; ;; my $c = ['bar']; print @{$c}[0]; print @ $c [0]; " Scalar value @c[0] better written as $c[0] at -e line 1. foo bar bar` [download]	[reply] [d/l]
Re^10: Perl list items by Anonymous Monk on Jul 10, 2012 at 09:24 UTC
I'm still puzzled by the absence of a "... better written as ..." warning. Because the code is different :) Because @warnme... is different from @$derefNowarn... For verbosity see diagnostics, try `perl -Mdiagnostics -e " @ARGV[0] "`	[reply] [d/l]
Re^11: Perl list items by AnomalousMonk (Archbishop) on Jul 10, 2012 at 10:36 UTC
Because the code is different :) True, the code is different, but the expressions are all equivalent: they're all 'degenerate' single-item slices. Because @warnme... is different from @$derefNowarn... I don't understand the significance of this statement. Are scalar derefs in this context (single-item slices) simply not warned about? If so, is there a rationale for this? (I could understand if this was simply beyond the scope of the `warnings` system as it now stands. After all, you can't warn about everything.) For verbosity see diagnostics... `diagnostics` are indeed more verbose, but don't throw more light, for me, on this (admittedly somewhat trivial) problem. Oh well, going to bed now...	[reply] [d/l] [select]