More like 1. $SIG{__WARN__} allows me to decide what to do with my warnings at some later time, without needing to substitute every warn() call if I need things differently. See %SIG.
# debugger, please slow down when you see keyword
$SIG{__WARN__} = sub { $DB::single = $_[0] =~ /keyword/; warn(@_) }

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In reply to Re^3: using warn instead or print STDERR? by repellent
in thread using warn instead or print STDERR? by leocharre

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