range problems

[ToddAndMargo via perl6-users]

Hi Al,

Now what am I doing wrong?

> my Int $u = 0xF8; say $u.Range;

Invocant of method 'Range' must be a type object of
type 'Int', not an object instance of type 'Int'.
Did you forget a 'multi'?

When is an Int not an Int?

Perplexed,
-T

range doc page

[ToddAndMargo via perl6-users]

Hi All,

On https://docs.raku.org/routine/range, it states:

method range(--> Range:D)

What is being said?

   method I understand.

   Range would be the name of the method

   --> means is return the range of what was fed the
   method and is defined


This one ain't all the hard to decipher.

So why does this not work?

> my int8 $u = 0xF8; $u.range

No such method 'range' for invocant of type 'Int'. Did you mean any of 
these?

Range
rand


Perplexed,
-T

range doc page

[ToddAndMargo via perl6-users]

Perplexed,
-THi All,

On https://docs.raku.org/routine/range, it states:

method range(--> Range:D)

What is being said?

   method I understand.

   Range would be the name of the method

   --> means is return the range of what was fed the
   method and is defined


This one ain't all the hard to decipher.

So why does this not work?

> my int8 $u = 0xF8; $u.range

No such method 'range' for invocant of type 'Int'. Did you mean any of 
these?

Range
rand


Perplexed,
-T

Re: range doc page

[Kevin Pye]

There's no need to ask essentially the same question three times.

https://docs.raku.org/routine/range 
is quite clearly the wrong page. That's about a method on the class
X::OutOfRange, and not a method on Int. You want
https://docs.raku.org/routine/Range, which will unfortunately not be much
more useful.

Your original error message "Invocant of method 'Range' must be a type
object of
type 'Int', not an object instance of type 'Int'" is much more useful.

Your variable $u contains a variable of type Int. What the method Range
wants is a "type object of type 'Int'" which is not the same thing.This is
what you would get with a definition like "my UInt $u;". $u is now a
variable containing no definite value, but is of type UInt. If you were to
"say $u" you would get "(UInt)", which is a type object. "say $u.Range"
would then give "0..^Inf".

This is related to the ":D" and ":U" forms in signatures. "sub x(Int:D
$arg)" would require the subroutine to be passed an actual object of type
Int. "sub y(Int:U $arg)" would need to be passed a "type object of type
'Int'". If you were to check the source you would find the signature of
Range to be something like "method Range(Int:U --> Range)".

Kevin.

On Tue, 28 Jan 2020 at 16:09, ToddAndMargo via perl6-users <
perl6-us...@perl.org> wrote:

> Hi All,
>
> On https://docs.raku.org/routine/range, it states:
>
> method range(--> Range:D)
>
> What is being said?
>
> method I understand.
>
> Range would be the name of the method
>
> --> means is return the range of what was fed the
> method and is defined
>
>
> This one ain't all the hard to decipher.
>
> So why does this not work?
>
>  > my int8 $u = 0xF8; $u.range
>
> No such method 'range' for invocant of type 'Int'. Did you mean any of
> these?
>  Range
>  rand
>
>
> Perplexed,
> -T
>