use of typeof to determine auto type with ndslice examples
I pulled down the std.experimental.ndslice examples and am
attempting to build some of the examples and understand the types
being used.
I know don't need all these imports, but it is hard to guess
which ones are needed, and the examples often don't provide them,
which I suspect is a common gripe here.
Anyway, I was expecting to be able to use the typeof pragma to
print a type that could use as a fully specified type, and that
doesn't seem to be the case. I get a compile error instead.
DMD32 D Compiler v2.069.2 on win32, "dip80-ndslice": "~>0.8.4"
Is there some other way to get a valid fully specified type for
these sliced auto variables?
import std.stdio;
import std.experimental.ndslice;
void main() {
import std.algorithm.iteration: map;
import std.array: array;
import std.range;
import std.traits;
auto t0 = 1000.iota.sliced(3, 4, 5);
pragma(msg, typeof(t0));
Slice!(3u, Result) = 1000.iota.sliced(3, 4, 5);
Slice!(3u, Result)
src\app.d(12,2): Error: undefined identifier 'Result'
dmd failed with exit code 1.
Re: use of typeof to determine auto type with ndslice examples
So, the extra confusion of the typeof(iota) Result return goes away when slicing arrays. auto a1 = new int[100]; auto t3 = a1.sliced(3,4,5); pragma(msg,typeof(t3)); //This prints Slice!(3u, int*) Slice!(3u, int*) t4 = a1.sliced(3,4,5); // and this works ok
Re: use of typeof to determine auto type with ndslice examples
On Monday, 21 December 2015 at 04:20:16 UTC, Jay Norwood wrote:
I pulled down the std.experimental.ndslice examples and am
attempting to build some of the examples and understand the
types being used.
I know don't need all these imports, but it is hard to guess
which ones are needed, and the examples often don't provide
them, which I suspect is a common gripe here.
Anyway, I was expecting to be able to use the typeof pragma to
print a type that could use as a fully specified type, and that
doesn't seem to be the case. I get a compile error instead.
DMD32 D Compiler v2.069.2 on win32, "dip80-ndslice": "~>0.8.4"
Is there some other way to get a valid fully specified type for
these sliced auto variables?
import std.stdio;
import std.experimental.ndslice;
void main() {
import std.algorithm.iteration: map;
import std.array: array;
import std.range;
import std.traits;
auto t0 = 1000.iota.sliced(3, 4, 5);
pragma(msg, typeof(t0));
Slice!(3u, Result) = 1000.iota.sliced(3, 4, 5);
Slice!(3u, Result)
src\app.d(12,2): Error: undefined identifier 'Result'
dmd failed with exit code 1.
No way that I know of. I've had this before with iota and its
various forms. I have done this in the past:
(or something similar, I haven't got my code handy ATM)
---
alias RESULT = typeof(iota(1, 2, 3));
...
Slice!(3u, RESULT) = 1000.iota.sliced(3, 4, 5);
---
Note that iota(1) and iota(1, 2, 3) return different types so you
would require two different RESULT aliases.
bye,
lobo
Re: use of typeof to determine auto type with ndslice examples
21.12.2015 07:23, Jay Norwood пишет:
import std.stdio;
import std.experimental.ndslice;
void main() {
import std.algorithm.iteration: map;
import std.array: array;
import std.range;
import std.traits;
auto t0 = 1000.iota.sliced(3, 4, 5);
pragma(msg, typeof(t0));
Slice!(3u, Result) t1 = 1000.iota.sliced(3, 4, 5);
darn, I didn't duplicate the problem correctly. It should be as above.
and the error is:
Slice!(3u, Result)
src\app.d(12,2): Error: undefined identifier 'Result'
dmd failed with exit code 1.
You can use
alias Type = typeof(t0);
Type t1 = 1000.iota.sliced(3, 4, 5);
IIRC Result is the Voldemort type. You can think of it as a detail of
implementation of ndslice that isn't intended to be used by a ndslice
user directly.
Re: use of typeof to determine auto type with ndslice examples
import std.stdio;
import std.experimental.ndslice;
void main() {
import std.algorithm.iteration: map;
import std.array: array;
import std.range;
import std.traits;
auto t0 = 1000.iota.sliced(3, 4, 5);
pragma(msg, typeof(t0));
Slice!(3u, Result) t1 = 1000.iota.sliced(3, 4, 5);
darn, I didn't duplicate the problem correctly. It should be as
above.
and the error is:
Slice!(3u, Result)
src\app.d(12,2): Error: undefined identifier 'Result'
dmd failed with exit code 1.
Re: use of typeof to determine auto type with ndslice examples
On Monday, 21 December 2015 at 04:39:23 UTC, drug wrote: You can use alias Type = typeof(t0); Type t1 = 1000.iota.sliced(3, 4, 5); IIRC Result is the Voldemort type. You can think of it as a detail of implementation of ndslice that isn't intended to be used by a ndslice user directly. ok, well this worked, so it seems to be something lacking in the description of iota's type rather than an issue with ndslice. alias RESULT = typeof(1000.iota); Slice!(3u, RESULT) t1 = 1000.iota.sliced(3, 4, 5); auto t2 = 1000.iota(); pragma(msg, typeof(t2)); This just prints Result. Ok, so what is the reason for not being able to know the type of a specified iota?
