[forwarded submission from a non-member address -- rjk]
From: Damian Conway <[EMAIL PROTECTED]>
Date: Fri, 6 Jul 2001 02:41:32 +1000 (EST)
Subject: Re: array and hash slices in Perl 6
To: Boston Perl Mongers <[EMAIL PROTECTED]>,
"Tolkin,
Steve" <[EMAIL PROTECTED]>
> I would have tried to ask Damian the following technical questions.
> Perhaps someone else can ask it, or ever answer it here in email.
>
> Larry says the syntax for hash slices and array slices will
> change in Perl 6. Does anyone know at this point what the new
> syntax for array slices and hash slices looks like?
Very probably like I described in Exegesis 2:
@array[@indices]
%hash[@keys]
> Will it be possible to automatically translate the Perl 5 to Perl 6?
95% possible, yes. Certainly standard slices will translate.
> I have a program that makes heavy use of this very powerful feature.
> Here are some excerpts. First is a simple example of hash slice usage:
>
> @f{@mff_feed_cols} = split(/\|/, $line );
This will become:
%f{@mff_feed_cols} = split(/\|/, $line );
Whilst:
> if ( join( $sep, @{$fields[old]}[@{$compareindexlist[old]}] ) eq
> join( $sep, @{$fields[new]}[@{$compareindexlist[new]}] ) )
will become:
if ( join( $sep, @{@fields[old]}[@{@compareindexlist[old]}] ) eq
join( $sep, @{@fields[new]}[@{@compareindexlist[new]}] ) )
or perhaps even just:
if ( join( $sep, @fields[old][@compareindexlist[old]] ) eq
join( $sep, @fields[new][@compareindexlist[new]] ) )
(if Larry decides that array refs will auto-derefence everywhere)
Damian
