Why does perl not warn when redeclaring a variable in an inner scope? -


as bit of perl novice, ran bug accidentally did (example simplified):

my $i=0;  for(my $i=0;$i<10; $i++)   {     print $i;   } print $i; # $i zero, code expected 9

from why don't warning when redeclare perl foreach control variable? understand behavior expected; should not warning unless re-declaration in same scope.

however, can not understand why case. why perl not issue warning here? seems me cause of errors, , not intended. there common case normal programming style, warning annoying?

perl doesn't tend warn style issues, find hard believe intentionally want have same var name @ different scope depths.

the case might useful comes mind is

{     $x = $x;     ... changes $x ... } # $x restored here.

on plus side, there perlcritic rule identify such problem.


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