>perl -wMstrict -le
"for my $string (qw(x 1x 12x 987x)) {
   print qq{string '$string' in numeric context is == }, 0+$string;
   }
"
Argument "x" isn't numeric in addition (+) at -e line 1.
string 'x' in numeric context is == 0
Argument "1x" isn't numeric in addition (+) at -e line 1.
string '1x' in numeric context is == 1
Argument "12x" isn't numeric in addition (+) at -e line 1.
string '12x' in numeric context is == 12
Argument "987x" isn't numeric in addition (+) at -e line 1.
string '987x' in numeric context is == 987