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Postings from June 2020
BEGIN trait_mod:<is>(&any, :tighter(&infix:<*>));
comes to mind, but that doesn't seem to do the trick.
> On 22 Jun 2020, at 21:11, Tobias Boege <tobs@taboege.de> wrote:
>
> On Mon, 22 Jun 2020, Joseph Brenner wrote:
>> Patrick R. Michaud <pmichaud@pobox.com> wrote:
>>
>>> The "any" function is just like any other function taking an arbitrary list
>>> of arguments (including user-defined functions). As such it parses with
>>> lower precedence than comparison operators -- so "eq" binds more tightly
>>> than "any".
>>
>> Thanks, makes sense.
>>
>>> I'm not exactly sure what sort of warning should go here, or how it'd be
>>> detected.
>>
>> Yes, exactly. From one point of view it's working as designed-- to me
>> it felt pretty weird, though.
>>
>> Speculating wildly: could there be a need for a different type of
>> function with different precedence?
>>
>
> You can achieve this today by redefining &any to be a prefix operator
> and provide it with tight enough precedence. In this example, I pick
> infix multiplication as the argument stopper, which is in particular
> tighter than the relevant eq operator; your mileage may vary:
>
> sub old-any (|c) { CORE::{'&any'}.(|c) }
>
> multi prefix:<any> (|c) is tighter(&infix:<*>) {
> old-any |c
> }
>
> say so any <a b c> eq any <c d>; # True (fixed)
> say so old-any(<a b c>) eq old-any(<c d>); # True
> say so old-any <a b c> eq old-any <c d>; # False
>
> Now I'd be interested to see how someone would turn this into a
> frugal-sub declarator or an `is frugal` trait.
>
> Regards,
> Tobias
>
> --
> "There's an old saying: Don't change anything... ever!" -- Mr. Monk
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