Re: std.algorithm.among
Ola Fosheim Grøstad: On Sunday, 13 July 2014 at 20:55:25 UTC, bearophile wrote: D doesn't carry the range of mutable variables across different expressions. What is the reasoning behind this kind of special-casing? Compiler simplicity and to avoid flow analysis. The value range is kept across const expressions since 2.066. Bye, bearophile
std.algorithm.among
The idea of not making std.algorithm.among!() a predicate was not
so good:
void main() {
import std.stdio, std.algorithm;
auto s = hello how\nare you;
s.until!(c = c.among!('\n', '\r')).writeln;
}
(A normal workaround is to use !!c.among!).
Bye,
bearophile
Re: std.algorithm.among
On Sunday, 13 July 2014 at 11:18:05 UTC, bearophile wrote:
The idea of not making std.algorithm.among!() a predicate was
not so good:
void main() {
import std.stdio, std.algorithm;
auto s = hello how\nare you;
s.until!(c = c.among!('\n', '\r')).writeln;
}
(A normal workaround is to use !!c.among!).
Bye,
bearophile
```
s.until!(among!('\n', '\r')).writeln; // Error: cannot implicitly
convert expression (among(front(this._input))) of type uint to
bool
```
:-(
Re: std.algorithm.among
On 07/13/2014 01:18 PM, bearophile wrote:
The idea of not making std.algorithm.among!() a predicate was not so good:
...
Agreed.
void main() {
import std.stdio, std.algorithm;
auto s = hello how\nare you;
s.until!(c = c.among!('\n', '\r')).writeln;
}
(A normal workaround is to use !!c.among!).
Bye,
bearophile
It works with filter, so I think it should just work with until as well.
Re: std.algorithm.among
Timon Gehr: It works with filter, so I think it should just work with until as well. So do you suggest me to open a bug report where I ask among to return a bool, or do you suggest to ask for an enhancement of until, or what? Bye, bearophile
Re: std.algorithm.among
Timon Gehr:
I am saying the following code implementing 'until' in
std.algorithm is at fault:
private bool predSatisfied() // -- don't say bool here
{
static if (is(Sentinel == void))
return unaryFun!pred(_input.front); // or cast here
else
return startsWith!pred(_input, _sentinel); // and
here
}
https://issues.dlang.org/show_bug.cgi?id=13124
Bye,
bearophile
Re: std.algorithm.among
On Sunday, 13 July 2014 at 11:18:05 UTC, bearophile wrote:
The idea of not making std.algorithm.among!() a predicate was
not so good:
void main() {
import std.stdio, std.algorithm;
auto s = hello how\nare you;
s.until!(c = c.among!('\n', '\r')).writeln;
}
(A normal workaround is to use !!c.among!).
Bye,
bearophile
That's weird, I always assumed this worked. Was it always the
case that numeric types can't be implicitly casted to bool?
Re: std.algorithm.among
On 07/13/2014 08:51 PM, Meta wrote: That's weird, I always assumed this worked. Was it always the case that numeric types can't be implicitly casted to bool? Yes, unless their range fits into [0,2).
Re: std.algorithm.among
On Sunday, 13 July 2014 at 19:06:29 UTC, Timon Gehr wrote:
On 07/13/2014 08:51 PM, Meta wrote:
That's weird, I always assumed this worked. Was it always the
case that
numeric types can't be implicitly casted to bool?
Yes, unless their range fits into [0,2).
It seems that not even that is the case.
void main()
{
uint n = 0;
//Error
bool b = n;
}
Re: std.algorithm.among
Meta:
It seems that not even that is the case.
void main()
{
uint n = 0;
//Error
bool b = n;
}
D doesn't carry the range of mutable variables across different
expressions.
So write (with the 2.066beta3):
void main() {
const uint x1 = 0;
const uint x2 = 1;
bool b1 = x1;
bool b2 = x2;
}
Bye,
bearophile
Re: std.algorithm.among
On Sunday, 13 July 2014 at 20:55:25 UTC, bearophile wrote: D doesn't carry the range of mutable variables across different expressions. What is the reasoning behind this kind of special-casing?
