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.  :'(

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