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[perl #132557] improvements in perldata

From:
James E Keenan via RT
Date:
December 19, 2017 18:19
Subject:
[perl #132557] improvements in perldata
Message ID:
rt-4.0.24-23483-1513707577-1436.132557-15-0@perl.org
On Sun, 10 Dec 2017 04:36:21 GMT, calestyo@scientia.net wrote:
> 
> This is a bug report for perl from calestyo@scientia.net,
> generated with the help of perlbug 1.40 running under perl 5.26.1.
> 
> 
> -----------------------------------------------------------------
> Hi.
> 
> perldata describes quite a lot about slices, list assignments and that
> like.
> 
> I think it misses the following things (or could clarify on them):
> 
> 
> 1) It tells what happens when one does a list assignment in scalar
> context,
>    e.g.:
>    $count = $string =~ /\d+/g;
> 
> At the same point it should also tell, what happens for list
> assignment
> in list context.
> 
> 
> 2) It tells that a list evaluated in scalar context, evaluates all
> it's
>    elements (actually this is IIRC only mentioned in perlop) and that
>    the last element get's assigned (all others discarded).
> 
> I think it could also tell that this is the case for list slices, e.g.
> $b = (1, 2, 3, 4)[0, 3];
> now b is 4
> While this is still kinda "obvious" or what one could expect, the
> following
> is not necessarily so clear:
> @a=(1, 2, 3, 4);
> $b = @a[0, 3];
> now b is four as well.
> 
> AFAICS, it tells no where, that this would happen for array slices.
> A reader may likely assume, that an array slice behaves like or is
> an array and should thus - in scalar context - return the lenght.
> 
> Actually it seems that slices generally behave more like lists than
> like arrays, e.g. in the case of:
> @colors{'red','blue','green'} = (0xff0000, 0x0000ff, 0x00ff00);
> where the left hand side is not evaluated like an array, but like a
> list
> where one can assign to the elements of it.
> 
> I think this (that slices are like lists) should perhaps be emphasised
> more.
> 
> What about hash slices?
> 
> 

I've read this ticket several times.  Each time my impression has been "this ticket is all over the place".  It is very diffuse in its complaints.

I'm inclined to reject it unless the original poster can provide patches to the pod/*.pod files of concern.

Thank you very much.

-- 
James E Keenan (jkeenan@cpan.org)

---
via perlbug:  queue: perl5 status: new
https://rt.perl.org/Ticket/Display.html?id=132557



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