Re: std.random question

[Dennis Ritchie via Digitalmars-d-learn]

On Sunday, 3 May 2015 at 09:04:07 UTC, tired_eyes wrote:

On Sunday, 3 May 2015 at 08:48:52 UTC, Dennis Ritchie wrote:

On Sunday, 3 May 2015 at 08:42:57 UTC, tired_eyes wrote:

Feels pretty silly, but I can't compile this:


import std.random;
auto i = uniform(0, 10);


DMD spits this:

/usr/include/dmd/phobos/std/random.d(1188): Error: static 
variable initialized cannot be read at compile time
/usr/include/dmd/phobos/std/random.d(1231):called 
from here: rndGen()
/usr/include/dmd/phobos/std/random.d(1231):called 
from here: uniform(a, b, rndGen())



Perhaps I'm missing something obvious?
dmd 2.067.1, openSUSE 13.2 x64


void main() {
import std.random;
auto i = uniform(0, 10);
}


Not so simple, unfortunately.
Actual code:


import std.random;

struct Mystruct {
auto id = uniform(0, 10);
}

void main() {
// wahtever
}


..and no luck.


I think it is a bug:

import std.stdio, std.random;

struct Mystruct {
//mixin(`auto id = uniform(0, 10);`);
	// Error: static variable initialized cannot be read at compile 
time

int val;
}

void main() {

Mystruct test;

test.val = uniform(0, 10); // OK
writeln(test.val);

mixin(`auto n = uniform(0, 10);`); // OK
}

Re: std.random question

[Dennis Ritchie via Digitalmars-d-learn]

On Sunday, 3 May 2015 at 08:42:57 UTC, tired_eyes wrote:

Feels pretty silly, but I can't compile this:


import std.random;
auto i = uniform(0, 10);


DMD spits this:

/usr/include/dmd/phobos/std/random.d(1188): Error: static 
variable initialized cannot be read at compile time
/usr/include/dmd/phobos/std/random.d(1231):called from 
here: rndGen()
/usr/include/dmd/phobos/std/random.d(1231):called from 
here: uniform(a, b, rndGen())



Perhaps I'm missing something obvious?
dmd 2.067.1, openSUSE 13.2 x64


void main() {
import std.random;
auto i = uniform(0, 10);
}

Re: std.random question

[tired_eyes via Digitalmars-d-learn]

On Sunday, 3 May 2015 at 08:48:52 UTC, Dennis Ritchie wrote:

On Sunday, 3 May 2015 at 08:42:57 UTC, tired_eyes wrote:

Feels pretty silly, but I can't compile this:


import std.random;
auto i = uniform(0, 10);


DMD spits this:

/usr/include/dmd/phobos/std/random.d(1188): Error: static 
variable initialized cannot be read at compile time
/usr/include/dmd/phobos/std/random.d(1231):called from 
here: rndGen()
/usr/include/dmd/phobos/std/random.d(1231):called from 
here: uniform(a, b, rndGen())



Perhaps I'm missing something obvious?
dmd 2.067.1, openSUSE 13.2 x64


void main() {
import std.random;
auto i = uniform(0, 10);
}


Not so simple, unfortunately.
Actual code:


import std.random;

struct Mystruct {
auto id = uniform(0, 10);
}

void main() {
// wahtever
}


..and no luck.

Re: std.random question

[tired_eyes via Digitalmars-d-learn]

import std.random;

struct Mystruct {
int id;

static opCall() {
Mystruct s;
s.id = uniform(0, 10);
return s;
}
}

void main() {
auto s = Mystruct();
// whatever
}
---


This make sense, thant you for the explanation.

Re: std.random question

[tired_eyes via Digitalmars-d-learn]

Hmmm.

hap.random from http://code.dlang.org/packages/hap behaves 
exactly the same.

Re: std.random question

[biozic via Digitalmars-d-learn]

On Sunday, 3 May 2015 at 09:28:40 UTC, Dennis Ritchie wrote:

On Sunday, 3 May 2015 at 09:04:07 UTC, tired_eyes wrote:

On Sunday, 3 May 2015 at 08:48:52 UTC, Dennis Ritchie wrote:

On Sunday, 3 May 2015 at 08:42:57 UTC, tired_eyes wrote:

Feels pretty silly, but I can't compile this:


import std.random;
auto i = uniform(0, 10);


DMD spits this:

/usr/include/dmd/phobos/std/random.d(1188): Error: static 
variable initialized cannot be read at compile time
/usr/include/dmd/phobos/std/random.d(1231):called 
from here: rndGen()
/usr/include/dmd/phobos/std/random.d(1231):called 
from here: uniform(a, b, rndGen())



Perhaps I'm missing something obvious?
dmd 2.067.1, openSUSE 13.2 x64


void main() {
import std.random;
auto i = uniform(0, 10);
}


Not so simple, unfortunately.
Actual code:


import std.random;

struct Mystruct {
   auto id = uniform(0, 10);
}

void main() {
   // wahtever
}


..and no luck.


I think it is a bug:


No. The aboc code defines a field of Mystruct calld 'id', with a 
type inferred from the static initializer expression 'uniform(0, 
10)'. The problem is that a static initializer is... static! So 
the expression must be evaluated at compile-time. The uniform 
generator from std.random cannot be used at compile-time, thus 
the error.


You could do:
---
import std.random;

struct Mystruct {
int id;

static opCall() {
Mystruct s;
s.id = uniform(0, 10);
return s;
}
}

void main() {
auto s = Mystruct();
// whatever
}
---