I think you should be using <{ }> rather than {}. If it was working before
then that was probably a bug :\. They are both succeeding because it's
essentially matching against an empty regex. the return value of <{ ... }>
is actually used for matching.
See: http://design.perl6.org/S05.html
It's
# New Ticket Created by "Carl Mäsak"
# Please include the string: [perl #126532]
# in the subject line of all future correspondence about this issue.
# https://rt.perl.org/Ticket/Display.html?id=126532 >
Basically, any argument containing only whitespace seems to trigger
this error. It seems
Branch: refs/heads/master
Home: https://github.com/perl6/specs
Commit: e1da64feaf3cb87130c860a492f9a4876f2dfe77
https://github.com/perl6/specs/commit/e1da64feaf3cb87130c860a492f9a4876f2dfe77
Author: Jonathan Stowe
Date: 2015-11-01 (Sun, 01 Nov 2015)