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Raku
Clarify use of Raku's 'any' versus that of Perl
Given a Perl statement:
my $b = any { $_ < 0 } @args;
how does that translate to Raku?
On Mar 12, 2021, at 3:32 PM, Tom Browder @.***> wrote:
Given a Perl statement:
my $b = any { $_ < 0 } @args;
how does that translate to Raku?
my $b = so @a.any < 0;
raku -e 'my @a = 0, 2, 5; say so @a.any < 0;' False
raku -e 'my @a = 0, -2, 5; say so @a.any < 0;' True
https://docs.raku.org/routine/so https://docs.raku.org/routine/any https://docs.raku.org/type/Junction
The so is needed to collapse the Junction to a simple Boolean (and probably allow short-circuiting):
raku -e 'my @a = 0, -2, 5; say @a.any < 0;'
any(False, True, False)
A question-mark boolean coercer would be too high-precedence to work there without parens.
Jonathan Stowe’s suggestion of: @.*( < 0) also looks good to me, but because .first returns Nil on failure, I would state it as: @args.first( < 0).defined
-- Hope this helps, Bruce Gray (Util of PerlMonks)
but because .first returns Nil on failure, I would state it as
Which is why the ? to boolify the Nil :-D
Maybe we could put this in one of the Perl pages?
Yeah, List::Util is virtually ubiquitous. It's almost like there should be a page with "things that are builtin in raku that required modules in Perl"
Yes, and it works great, along with Time::gmtime, both Butterfly modules thanks to our famous and prolific Raku developer @lizmat!!
From the style guide:
### Don't reference Perl unless in a 5-to-6 document or related document
We are not expecting our users to have to know Perl to learn Raku,
so this should not be part of the bulk of the documentation.
