• =?UTF-8?B?IsOYaXZpbmQi?= (13/13) Sep 08 2013 I find myself writing the following a lot:
• =?UTF-8?B?IsOYaXZpbmQi?= (2/3) Sep 08 2013 I think this should be
• Chang Long (2/6) Sep 08 2013 try &a[base][0..width]
• Simen Kjaeraas (6/14) Sep 08 2013 That throws safety out the window for one. If you want safety and
• =?UTF-8?B?IsOYaXZpbmQi?= (7/23) Sep 08 2013 Thanks
• Walter Bright (3/11) Sep 08 2013 Try it and see. If it isn't, feel free to file an enhancement request fo...

=?UTF-8?B?IsOYaXZpbmQi?= <oivind.loe gmail.com> writes:

I find myself writing the following a lot:

   a[base..base+width]

to get the slice starting at 'base' of width 'width'. In verilog, 
we select members of a vector/array in three ways

   a[c :  d]   //D: a[c   .. d+1]
   a[c +: d]   //D: a[c   .. c+d]
   a[c -: d]   //D: a[c-d .. c]

Borrowing a bit from verilog, could we make two new operators, 
maybe +.. and -.. that allow us to do the same?

I could then write e.g.

   a[base+..width]

instead of the more verbose

   a[base..base+width]

=?UTF-8?B?IsOYaXZpbmQi?= <oivind.loe gmail.com> writes:

   a[c -: d]   //D: a[c-d .. c]

I think this should be

a[c -: d]   //D: a[c-d+1 .. c+1],  e.g. a[5 -: 2] == [a[4], a[5]]

"Chang Long" <changlon gmail.com> writes:

On Sunday, 8 September 2013 at 10:53:23 UTC, Øivind wrote:
  a[c -: d]   //D: a[c-d .. c]

 I think this should be

 a[c -: d]   //D: a[c-d+1 .. c+1],  e.g. a[5 -: 2] == [a[4], 
 a[5]]


try &a[base][0..width]

"Simen Kjaeraas" <simen.kjaras gmail.com> writes:

On 2013-09-08, 14:02, Chang Long wrote:

 On Sunday, 8 September 2013 at 10:53:23 UTC, =C3=98ivind wrote:
  a[c -: d]   //D: a[c-d .. c]

 I think this should be

 a[c -: d]   //D: a[c-d+1 .. c+1],  e.g. a[5 -: 2] =3D=3D [a[4], a[5]]=


 try &a[base][0..width]

That throws safety out the window for one. If you want safety and
no new language features, this should work:

   a[base..$][0..width]

-- =

   Simen

=?UTF-8?B?IsOYaXZpbmQi?= <oivind.loe gmail.com> writes:

On Sunday, 8 September 2013 at 12:08:50 UTC, Simen Kjaeraas wrote:
 On 2013-09-08, 14:02, Chang Long wrote:

 On Sunday, 8 September 2013 at 10:53:23 UTC, Øivind wrote:
 a[c -: d]   //D: a[c-d .. c]

 I think this should be

 a[c -: d]   //D: a[c-d+1 .. c+1],  e.g. a[5 -: 2] == [a[4], 
 a[5]]


 try &a[base][0..width]

 That throws safety out the window for one. If you want safety 
 and
 no new language features, this should work:

   a[base..$][0..width]

Thanks

Still a little verbose, but at least you don't have to type the 
same things twice.

I guess the double slice will be optimized into a single one at 
least for release mode, so there should be no performance 
degredation?

Walter Bright <newshound2 digitalmars.com> writes:

On 9/8/2013 6:03 AM, "Øivind" wrote:
 That throws safety out the window for one. If you want safety and
 no new language features, this should work:

   a[base..$][0..width]

 Thanks

 Still a little verbose, but at least you don't have to type the same things
twice.

 I guess the double slice will be optimized into a single one at least for
 release mode, so there should be no performance degredation?


Try it and see. If it isn't, feel free to file an enhancement request for the 
optimizer!