Assinging to $_ without localizing it is dangerous.
(local $_ = $before) =~ s/^\s+|\s+$//g;
or
(my $after = $before) =~ s/^\s+|\s+$//g;
should be used in just almost all cicumstances.

In reply to Re^2: what is the function should I need to use for trim white spaces ? by ikegami
in thread what is the function should I need to use for trim white spaces ? by jesuashok

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