'int' is enough for 'length' to migrate code from x86 to x64

ketmar via Digitalmars-d digitalmars-d at puremagic.com
Fri Nov 21 11:36:25 PST 2014


On Fri, 21 Nov 2014 10:59:13 -0800
Walter Bright via Digitalmars-d <digitalmars-d at puremagic.com> wrote:

> On 11/21/2014 6:03 AM, ketmar via Digitalmars-d wrote:
> > On Thu, 20 Nov 2014 13:28:37 -0800
> > Walter Bright via Digitalmars-d <digitalmars-d at puremagic.com> wrote:
> >
> >> On 11/20/2014 7:52 AM, H. S. Teoh via Digitalmars-d wrote:
> >>> What *could* be improved, is the prevention of obvious mistakes in
> >>> *mixing* signed and unsigned types. Right now, D allows code like the
> >>> following with no warning:
> >>>
> >>> 	uint x;
> >>> 	int y;
> >>> 	auto z = x - y;
> >>>
> >>> BTW, this one is the same in essence as an actual bug that I fixed in
> >>> druntime earlier this year, so downplaying it as a mistake people make
> >>> 'cos they confound computer math with math math is fallacious.
> >>
> >> What about:
> >>
> >>       uint x;
> >>       auto z = x - 1;
> >>
> >> ?
> >>
> > here z must be `long`. and for `ulong` compiler must emit error.
> 
> 
> So, any time an integer literal appears in an unsigned expression, the type of 
> the expression becomes signed?
nope. only for `auto` expressions.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 181 bytes
Desc: not available
URL: <http://lists.puremagic.com/pipermail/digitalmars-d/attachments/20141121/80d5477c/attachment.sig>


More information about the Digitalmars-d mailing list