develooper Front page | perl.perl6.users | Postings from February 2019

Re: "index" source code?

Thread Previous
From:
ToddAndMargo via perl6-users
Date:
February 3, 2019 22:07
Subject:
Re: "index" source code?
Message ID:
0fe8ad9a-4cc5-e944-2f0c-f62f5e168bf5@zoho.com
On 2/3/19 7:20 AM, Brad Gilbert wrote:
> The Rakudo Perl6 compilier is written in Perl6 (and a subset of Perl6 named NQP)
> 
> The `index` subroutines are at
> https://github.com/rakudo/rakudo/blob/64c88f919841c58f5a6dffd3581770e06a8fd6a5/src/core/Cool.pm6#L276-L282
> 
>      proto sub index($, $, $?, *%) {*}
>      multi sub index(Cool $s, Cool $needle --> Int:D) {
>          $s.index($needle)
>      }
>      multi sub index(Cool $s, Cool $needle, Cool $pos --> Int:D) {
>          $s.index($needle,$pos)
>      }
> 
> They basically only call the `index` and `rindex` methods
> 
> To keep from showing you all of the methods, they all coerce the value
> to Str then call `index` on that.
> 
> The location of the Str.index methods is
> https://github.com/rakudo/rakudo/blob/3d581c8d23e0b47fd09616a1165f84568531a4aa/src/core/Str.pm6#L255-L284
> 
>      proto method index(|) {*}
>      multi method index(Str:D: Cool:D $needle --> Int:D) {
>          self.index: $needle.Str
>      }
>      multi method index(Str:D: Str:D $needle --> Int:D) {
>          nqp::if(
>            nqp::islt_i((my int $i =
>              nqp::index($!value,nqp::getattr($needle,Str,'$!value'))),
>              0
>            ),
>            Nil,
>            nqp::p6box_i($i)
>          )
>      }
>      multi method index(Str:D: Cool:D $needle, Cool:D $pos --> Int:D) {
>          self.index: $needle.Str, $pos.Int
>      }
>      multi method index(Str:D: Str:D $needle, Int:D $pos --> Int:D) {
>          nqp::if(
>            nqp::isbig_I(nqp::decont($pos)) || nqp::islt_i($pos,0),
>            self!INDEX-OOR($pos),
>            nqp::if(
>              nqp::islt_i((my int $i = nqp::index(
>                $!value,nqp::getattr($needle,Str,'$!value'),$pos
>              )),0),
>              Nil,
>              nqp::p6box_i($i)
>            )
>          )
>      }
> 
> Note that they heavily use NQP opcodes, so you shouldn't try and copy them.
> 
> On Sun, Feb 3, 2019 at 12:35 AM ToddAndMargo via perl6-users
> <perl6-users@perl.org> wrote:
>>
>> Hi All,
>>
>> Was the subroutine "index" written Perl6?  If so,
>> where can I view the source code?
>>
>> Many thanks,
>> -T

Thank you!

The nqp op codes do seem way over my head.  :'(

Thread Previous


nntp.perl.org: Perl Programming lists via nntp and http.
Comments to Ask Bjørn Hansen at ask@perl.org | Group listing | About