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Postings from May 2013
On Mon, May 06, 2013 at 12:13:28PM +0200, demerphq wrote:
> On 6 May 2013 12:02, Dave Mitchell <davem@iabyn.com> wrote:
> > On Sun, May 05, 2013 at 11:45:25PM +0200, Sébastien Aperghis-Tramoni wrote:
> >> So, here is a proposal to try making this situation a bit better:
> >> annotate the SV to record the initial (or canonical) type of the the
> >> value, that is the type of the value that was last affected to the SV.
> >
> > But I don't think that necessarily solves the problem. Consider:
> >
> > while (<DATA>) {
> > chomp;
> > my ($x,$y) = split / /, $_;
> > my $z = sqrt($x*$x + $y*$y);
> > ... serialise $x, $y, $z;
> > }
> > __DATA__
> > 0.123 1.234
> > ...
> >
> > should $x, $y be serialised as strings or floats? I think the desire of
> > the programmer would be for them to be floats, but the canonical form is
> > string. In other words, the initial type still doesn't necessarily DWIM,
> > and its still up to the programmer to manually ensure the output is as
> > desired.
>
> Personally i think most serialization module authors would consider
> the canonical form to be the string, not the NV.
>
> Consider what should happen if the data line was
>
> __DATA__
> 0.123x 0.1234x
Yes, but my point is that serialization modules will often not do what the
user really intended, and using the canonical type doesn't fix that: it
just shuffles around the cases when it does and doesn't DWIM.
I think if it's important that something gets serialised in a particular
format, then in some way the programmer needs to tell the serialiser what
that format should be.
--
The optimist believes that he lives in the best of all possible worlds.
As does the pessimist.
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