I see two problems:
  1. The mixing of ' and ". Your single quotes around the '42' are the first thing breaking you
  2. The semicolon afte the if { } and before the else 
fappy@flux[62] tmp > perl -e 'if( q{42} =~ /[:^digit:]/) {print "42 is
+ a digit\n"} else {print "42 is not a digit\n"}';
42 is not a digit

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Now the questions remainns, what did you really want to test?

In reply to Re: POSIX-Style character classes by HuckinFappy
in thread POSIX-Style character classes by sub_chick

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