Thread overview
Example for Mir-Random fails
Apr 03
Brad
Apr 03
Preetpal
Apr 03
Brad
Apr 03
Brad
April 03

I just do not know enough about the D libraries to figure out what is wrong. I know it is a case of type mismatch. The example appears on the Mir-Random page as listed under DUB:
https://code.dlang.org/packages/mir-random

The code looks like this:

void main()
{
    import mir.random;
    import mir.random.variable: normalVar;
    import mir.random.algorithm: randomSlice;

    // Engines are allocated on stack or global
    auto rng = Random(unpredictableSeed);
    auto sample = rng.randomSlice(normalVar, 10);

    import std.stdio;
    sample[rng.randIndex($)].writeln;
}

This is the error I am seeing (I slapped the sample code into another program that flips a coin... It compiles file without the sample code):

source\flipcoin.d(39,20): Error: constructor `std.random.MersenneTwisterEngine!(uint, 32LU, 624LU, 397LU, 31LU, 2567483615u, 11LU, 4294967295u, 7LU, 2636928640u, 15LU, 4022730752u, 18LU, 1812433253u).MersenneTwisterEngine.this(uint value)` is not callable using argument types `(ulong)`
source\flipcoin.d(39,20):        cannot pass argument `unpredictableSeed()` of type `ulong` to parameter `uint value`

Obviously it is a type mismatch - I have tried using to!uint to convert the result from unpredictableSeed to a type that will match - but that just causes more errors.

Thank you in advance.

April 03

On Saturday, 3 April 2021 at 19:02:34 UTC, Brad wrote:

>

Obviously it is a type mismatch - I have tried using to!uint to convert the result from unpredictableSeed to a type that will match - but that just causes more errors.

Thank you in advance.

I was able to compile the sample without any issue and it was able to run. Can you give more information about your environment and possibly create a minimal example that re-creates the issue like in a Github repository?

April 03

On Saturday, 3 April 2021 at 19:02:34 UTC, Brad wrote:

>

I just do not know enough about the D libraries to figure out what is wrong. I know it is a case of type mismatch. The example appears on the Mir-Random page as listed under DUB:
https://code.dlang.org/packages/mir-random

[...]

I think you are seeing conflicts between Phobos and Mir: they both provide unpredictableSeed and Random. If you want to use the ones from Mir, be sure to not import std or std.random, or use fully qualified names.

— Bastiaan.

April 03

On Saturday, 3 April 2021 at 20:55:40 UTC, Preetpal wrote:

>

On Saturday, 3 April 2021 at 19:02:34 UTC, Brad wrote:

>

Obviously it is a type mismatch - I have tried using to!uint to convert the result from unpredictableSeed to a type that will match - but that just causes more errors.

Thank you in advance.

I was able to compile the sample without any issue and it was able to run. Can you give more information about your environment and possibly create a minimal example that re-creates the issue like in a Github repository?

I figured out that I had not purged all the Phobos random imports from my code and the issue was related to the two libraries not playing well together.

It is working now.

Interestingly though - the example code will not compile in the D Playground. I am not going to worry about that. It is working for me now.

Thanks

April 03

On Saturday, 3 April 2021 at 22:04:33 UTC, Bastiaan Veelo wrote:

>

On Saturday, 3 April 2021 at 19:02:34 UTC, Brad wrote:

>

I just do not know enough about the D libraries to figure out what is wrong. I know it is a case of type mismatch. The example appears on the Mir-Random page as listed under DUB:
https://code.dlang.org/packages/mir-random

[...]

I think you are seeing conflicts between Phobos and Mir: they both provide unpredictableSeed and Random. If you want to use the ones from Mir, be sure to not import std or std.random, or use fully qualified names.

— Bastiaan.

You nailed it. I just now figured that out. It never ceases to amaze me how much time can my lost to a simple mistake like that.

Thank you.