Missing docs for how to find the type of a native int

[zoffixznet]

I think there's some way to ask a variable for what type of native int it is (maybe something with metamodel?)

Don't see anything mentioned on https://docs.perl6.org/type/nativeInt

[Skarsnik]

You mean like checking if it's an int32 or something? I think only ^name can give you that. Native type are really weird. 2017-09-19 19:54 GMT+02:00 Zoffix Znet <notifications@github.com>:

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I think there's some way to ask a variable for what type of native int it is (maybe something with metamodel?) Don't see anything mentioned on https://docs.perl6.org/type/nativeInt — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#1568>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AMYVf9pI5tcLtv3LsrgdjC1piJ8_Bm6bks5sj__sgaJpZM4Pcx7q> .

-- Sylvain "Skarsnik" Colinet Victory was near but the power of the ring couldn't be undone

[zoffixznet]

I thought there was something, but perhaps it was the .^name.

It's not working for variables:

m: say int32.^name                                                                      rakudo-moar 083403: OUTPUT: «int32␤»
m: (my int32 $ = 42).^name.say                                                          rakudo-moar 083403: OUTPUT: «Int␤»

And I'm a bit surprised even this doesn't work. Gives Int for all the values:

my @vs := 42, (my int $ = 42), (my int32 $ = 42),
    (my int64 $ = 42), (my int16 $ = 42), (my int8 $ = 42);

multi wat (int)   { 'int'   }
multi wat (int8)  { 'int8'  }
multi wat (int16) { 'int16' }
multi wat (int32) { 'int32' }
multi wat (int64) { 'int64' }
multi wat (Int)   { 'Int'   }

.&wat.say for @vs;

[jnthn]

.^name is a meta-method call; to call a meta-method, we need an object to resolve the meta-object, and thus the native type is boxed into an Int and the call is done on that.

@vs is being bound to a List which holds objects, thus they are all boxed at the point of being made into a list.

Natives don't know their types because they're just values, without any meta-data. And sized natives only matter for storage; all operations are done at full width. So by the time you actually get a native in a position where you could pass it somewhere, it will be full-width anyway, so multi-dispatching over their size won't work out.

We might some day be able to make $some-native-var.VAR.of work out; at first I thought that was probably easy, then looked more closely and realized that no, not quite. You can, however, already as a native int array what kinds of elements it has, using my int32 @x = 42; say @x.of.

[JJ]

I see two options here. First, just close the issue, since there is no actual way to find the type of a native type. Second, to add the sentence by @jnthn

Natives don't know their types because they're just values, without any meta-data.
in an appropriate context, at least in the page that @zoffixznet has mentioned. I'd rather go for the first, but I'm open to arguments for the second (or any other option, for that matter)