I was just trying to run Simon Proctor's solution, and I see it
working for Yary's first case, but not his more complex one with
problem characters like brackets included in the list of characters.
I don't really see how to fix it, in part because I'm not that
clear on what it's actually doing... there's some sort of
implicit alternation going on?
sub contains( Str $chars, Str $_ ) {
m:g/<{$chars.comb}>+/
};
That works for this case:
say contains('24680', '19584203');
# (｢8420｣)
But on something like this it errors out:
say contains('+\/\]\[', 'Apple ][+//e'); # says ][+//
# ===SORRY!=== Error while compiling
/home/doom/End/Cave/Perl6/bin/trial-yary_building_char_class_from_array_chars.pl6
# Bogus statement
# at
/home/doom/End/Cave/Perl6/bin/trial-yary_building_char_class_from_array_chars.pl6:33
# ------> say contains('+\/\]\[', 'Apple ][+//e');⏏ # says ][+//
# expecting any of:
# prefix
# term
On 9/1/19, Simon Proctor <simon.proc...@gmail.com> wrote:
> sub contains ( Str $chars, Str $_ ) {
> m:g/<{$chars.comb}>+/
> };
>
> This will return all the sets of matching strings but it is doing runtime
> evaluation of your character string so it's a bit slow.
>
> On Sun, 1 Sep 2019 at 04:59, Paul Procacci <pproca...@gmail.com> wrote:
>
>> I'm not entirely sure if this is the correct answer, but if you define
>> your own custom character class
>> with a 'regex' object, you can use that in the grouping.
>>
>> sub matching_chars(Str $chars_to_match, Str $_) {
>> my regex x { $chars_to_match ** 1 };
>> m/<[<x>]>/;
>> }
>>
>> The above worked for me in the very small testing I did.
>>
>> ~Paul
>>
>> On Sat, Aug 31, 2019 at 9:54 PM yary <not....@gmail.com> wrote:
>>
>>> I found something easy in Perl 5 that's puzzling me in Perl 6-
>>> specifying
>>> a character class via a variable.
>>>
>>> Perl 5:
>>> sub matching_chars {
>>> (my $chars_to_match, local $_) = @_;
>>> /([$chars_to_match]+)/
>>> }
>>>
>>> say matching_chars('24680', '19584203'); # says 8420
>>> say matching_chars('+\/\]\[', 'Apple ][+//e'); # says ][+//
>>>
>>> Perl 6:
>>> sub matching_chars(Str $chars_to_match, Str $_) {
>>> # warnings, treats as string not variable
>>> m/<[$chars_to_match]>/;
>>> }
>>>
>>> How do I get Perl 6 to interpret a variable in the contents of a
>>> character class?
>>> From http://docs.perl6.org/language/regexes#Regex_interpolation I'd
>>> think that Rakudo would use the literal contents of $chars_to_match,
>>> instead it's using the literal chars "$ c h a r s _ t o _ m a t c h" and
>>> warning about repeated c, underscore, etc.
>>>
>>> -y
>>>
>>
>>
>> --
>> __________________
>>
>> :(){ :|:& };:
>>
>
>
> --
> Simon Proctor
> Cognoscite aliquid novum cotidie
>
> http://www.khanate.co.uk/
>
