Syntax error. You ask for one char, you get one char. The + needs to be within the capture and then it works as advertised. 

$_ =~ m[^([01]+)$] and print "$_:'$1'\n" for qw[ 0 1 00 11 10 01 012];
__DATA__
0:'0'
1:'1'
00:'00'
11:'11'
10:'10'
01:'01'

[download]

cheers

tachyon

In reply to Re: Regex failure interpretation by tachyon
in thread Regex failure interpretation by BrowserUk

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