• wjoe (28/28) Jul 13 2021 ```D
• =?UTF-8?Q?Ali_=c3=87ehreli?= (11/21) Jul 13 2021 If it's important, std.conv.to checks the value:
• wjoe (3/25) Jul 14 2021 I was planning on adding support for over-/underflow bits but
• =?UTF-8?Q?Ali_=c3=87ehreli?= (6/12) Jul 14 2021 If so, then there is also std.experimental.checkedint:
• wjoe (2/15) Jul 15 2021 Thanks I'll have a look.

wjoe <invalid example.com> writes:

```D
byte x = some_val;
long y = some_val;

x ^^= y; // Error:  cannot implicitly convert expression 
pow(cast(long)cast(int)x, y) of type long to byte
```

Is there a way to do this via ^^= ?

This is part of a unittest for opIndexOpAssign where the type of 
x is that of i.opIndex(_i). It's generated from a list of 
operators like this:

```D
part_int_t!(1, 8, 10) i;
static assert(is(typeof(i[0]): short));
static assert(is(typeof(i[1]): byte));
static assert(is(typeof(i[2]): bool));
static foreach(op; ["+=", "-=", "^^=", ...])
{{
   typeof(i[1]) x;
   mixin("x" ~ op ~ "y;");
   mixin("i[1]" ~ op ~ "y;");
   assert(i == x);
}}
```

I rewrote it to something like
```D
mixin("x = cast(typeof(x))(x" ~ op[0..$-1] ~ " y);");
```
but I'm curious if there's a less convoluted way.

=?UTF-8?Q?Ali_=c3=87ehreli?= <acehreli yahoo.com> writes:

On 7/13/21 4:12 AM, wjoe wrote:
 ```D
 byte x = some_val;
 long y = some_val;

 x ^^= y; // Error:  cannot implicitly convert expression
 pow(cast(long)cast(int)x, y) of type long to byte

[...]

 I rewrote it to something like
 ```D
 mixin("x = cast(typeof(x))(x" ~ op[0..$-1] ~ " y);");
 ```
 but I'm curious if there's a less convoluted way.

If it's important, std.conv.to checks the value:

import std.conv;

void main() {
   byte x = 2;
   long y = 6;
   x = (x ^^ y).to!(typeof(x));
}

For example, run-time error if y == 7.

Ali

wjoe <invalid example.com> writes:

On Tuesday, 13 July 2021 at 15:14:26 UTC, Ali Çehreli wrote:
 On 7/13/21 4:12 AM, wjoe wrote:
 ```D
 byte x = some_val;
 long y = some_val;

 x ^^= y; // Error:  cannot implicitly convert expression
 pow(cast(long)cast(int)x, y) of type long to byte

 [...]

 I rewrote it to something like
 ```D
 mixin("x = cast(typeof(x))(x" ~ op[0..$-1] ~ " y);");
 ```
 but I'm curious if there's a less convoluted way.

 If it's important, std.conv.to checks the value:

 import std.conv;

 void main() {
   byte x = 2;
   long y = 6;
   x = (x ^^ y).to!(typeof(x));
 }

 For example, run-time error if y == 7.

 Ali

I was planning on adding support for over-/underflow bits but 
this is much better. Thanks!

=?UTF-8?Q?Ali_=c3=87ehreli?= <acehreli yahoo.com> writes:

On 7/14/21 2:44 AM, wjoe wrote:

   x = (x ^^ y).to!(typeof(x));
 }

 For example, run-time error if y == 7.


 I was planning on adding support for over-/underflow bits but this is
 much better. Thanks!

If so, then there is also std.experimental.checkedint:

   https://dlang.org/phobos/std_experimental_checkedint.html

Andrei Alexandrescu introduced it in this presentation:

   https://dconf.org/2017/talks/alexandrescu.html

Ali

wjoe <invalid example.com> writes:

On Wednesday, 14 July 2021 at 17:29:04 UTC, Ali Çehreli wrote:
 On 7/14/21 2:44 AM, wjoe wrote:

   x = (x ^^ y).to!(typeof(x));
 }

 For example, run-time error if y == 7.


 I was planning on adding support for over-/underflow bits but

 this is
 much better. Thanks!

 If so, then there is also std.experimental.checkedint:

   https://dlang.org/phobos/std_experimental_checkedint.html

 Andrei Alexandrescu introduced it in this presentation:

   https://dconf.org/2017/talks/alexandrescu.html

 Ali

Thanks I'll have a look.