in reply to
Re^2: Perl 6 implementation of the following Perl 5 code
in thread Perl 6 implementation of the following Perl 5 code
It is "unspace". Whitespace is not allowed before subscripts or ".". Apparently this is required to allow "if" conditions without parens and is part of the "space is sometimes significant" path that was taken. (See: Synopsis 3 and the linked Synopsis 2)
Update: Below, moritz clarifies that "if" without parens was not the reason for forbidding whitespace around "." methods calls, merely another of the consequences.