Libguestfs - Jul 2016 - Re: [PATCH v3 4/8] mllib: Add some imperative list manipulation functions.

On Thursday 07 July 2016 17:30:03 Richard W.M. Jones
wrote:
> This adds imperative list manipulation functions inspired by Perl.
> The functions are passed list refs which get updated in place.
> 
> This allows us to replace some awkward pure functional code like:
> 
>   let xs = ys in
>   let xs = if foo then xs @ zs else xs in
> 
> with:
> 
>   let xs = ref ys in
>   if foo then append xs zs;
> ---
TBH I've always found the "shift" and "unshift" naming
of Perl
functions slightly awkward, but can live with them. (At least the
new functions do the same as Perl ones.)

-- 
Pino Toscano

On Thu, Jul 07, 2016 at 07:00:46PM +0200, Pino Toscano
wrote:
> On Thursday 07 July 2016 17:30:03 Richard W.M. Jones wrote:
> > This adds imperative list manipulation functions inspired by Perl.
> > The functions are passed list refs which get updated in place.
> > 
> > This allows us to replace some awkward pure functional code like:
> > 
> >   let xs = ys in
> >   let xs = if foo then xs @ zs else xs in
> > 
> > with:
> > 
> >   let xs = ref ys in
> >   if foo then append xs zs;
> > ---
> 
> TBH I've always found the "shift" and "unshift"
naming of Perl
> functions slightly awkward, but can live with them. (At least the
> new functions do the same as Perl ones.)
I agree, but for consistency I thought it was better to keep those
names rather than trying to think up new ones which would be different
from everything else.

Rich.


-- 
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On Thu, Jul 07, 2016 at 06:08:43PM +0100, Richard W.M. Jones
wrote:
> On Thu, Jul 07, 2016 at 07:00:46PM +0200, Pino Toscano wrote:
> > On Thursday 07 July 2016 17:30:03 Richard W.M. Jones wrote:
> > > This adds imperative list manipulation functions inspired by
Perl.
> > > The functions are passed list refs which get updated in place.
> > > 
> > > This allows us to replace some awkward pure functional code like:
> > > 
> > >   let xs = ys in
> > >   let xs = if foo then xs @ zs else xs in
> > > 
> > > with:
> > > 
> > >   let xs = ref ys in
> > >   if foo then append xs zs;
> > > ---
> > 
> > TBH I've always found the "shift" and
"unshift" naming of Perl
> > functions slightly awkward, but can live with them. (At least the
> > new functions do the same as Perl ones.)
> 
> I agree, but for consistency I thought it was better to keep those
> names rather than trying to think up new ones which would be different
> from everything else.
Actually I forgot that C++ (STL vector, deque etc) have functions
called push_front, pop_front, push_back, pop_back.  Don't know if that
would be better.  Is it obvious what front and back mean?

Rich.

-- 
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Read my programming and virtualization blog: http://rwmj.wordpress.com
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