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digitalmars.D.learn - Question about publishing a useful function I have written

reply Cecil Ward <cecil cecilward.com> writes:
I have written something which may or may not be novel and I’m 
wondering about how to distribute it to as many users as 
possible, hoping others will find it useful. What’s the best way 
to publish a D routine ?

It is called
     void assume( bool condition ) nothrow nogc safe

for example:
     assume( x < 100 );
or
     assume( y != 0 );

It generates no code at all, but t does tell the gdc compiler 
that the given condition is true and so later code generation may 
assume that truth in all code generation. So for example, given 
the assumes above,
     if ( x==200)
is false and no code is generated for the if-true basic block.

It might look a bit like assert but it isn’t the same thing. I 
think assert is disabled in full release build and is only there 
in debug mode, is that correct? Also assert generates code in 
that it calls panic or hits a ud2 or whatever, whereas assume is 
also zero code.

Does anyone know if this has already been published by someone 
else?

Unfortunately at the moment it only works with gdc as it relies 
on functions that are gdc-specific for its implementation. 
However I could use conditional compilation to simply set up a 
null implementation for other compilers.

I’d like to get it implemented with ldc if I can.


If anyone would like to give assume a try with gdc, then shout 
and I’ll try and find some way of getting it to you easily.
Jul 14 2020
next sibling parent reply Max Haughton <maxhaton gmail.com> writes:
On Tuesday, 14 July 2020 at 21:58:49 UTC, Cecil Ward wrote:

 I have written something which may or may not be novel and I’m 
 wondering about how to distribute it to as many users as 
 possible, hoping others will find it useful. What’s the best 
 way to publish a D routine ?

 [...]


GitHub is the best place to publish code. Does GDC actually use 
the optimization? I tried something like that before but I 
couldn't seem to get it to work properly.
Jul 14 2020
parent reply Cecil Ward <cecil cecilward.com> writes:
On Tuesday, 14 July 2020 at 23:10:28 UTC, Max Haughton wrote:

 On Tuesday, 14 July 2020 at 21:58:49 UTC, Cecil Ward wrote:

 I have written something which may or may not be novel and I’m 
 wondering about how to distribute it to as many users as 
 possible, hoping others will find it useful. What’s the best 
 way to publish a D routine ?

 [...]


 GitHub is the best place to publish code. Does GDC actually use 
 the optimization? I tried something like that before but I 
 couldn't seem to get it to work properly.


On Tuesday, 14
]

I just tried an experiment. It seems that in release mode 
assert()s are realised as absolutely nothing at all, and so the 
_conditions_ in the asserts are not declared. So later generated 
code does not have the benefit of knowledge of asserted truth 
conditions in release mode. So in release mode, without these 
truth conditions being established, the code generated (apart 
from the asserts’ code) can be _worse than in debug mode_, which 
seems bizarre, but it’s true.

for example
     assert( x < 100 );
     …
     if ( x==200 )  // <— evaluates to false _at compile time_
          {
          // no code generated for this block in debug mode,
          // but is generated in release mode
          }
     …
     if ( x < 100 ) // <— no code generated for if-test as cond == 
true at compile-time
Jul 15 2020
parent Andre Pany <andre s-e-a-p.de> writes:
On Wednesday, 15 July 2020 at 09:31:27 UTC, Cecil Ward wrote:

 On Tuesday, 14 July 2020 at 23:10:28 UTC, Max Haughton wrote:

 On Tuesday, 14 July 2020 at 21:58:49 UTC, Cecil Ward wrote:

 I have written something which may or may not be novel and 
 I’m wondering about how to distribute it to as many users as 
 possible, hoping others will find it useful. What’s the best 
 way to publish a D routine ?

 [...]


 GitHub is the best place to publish code. Does GDC actually 
 use the optimization? I tried something like that before but I 
 couldn't seem to get it to work properly.


 On Tuesday, 14
 ]

 I just tried an experiment. It seems that in release mode 
 assert()s are realised as absolutely nothing at all, and so the 
 _conditions_ in the asserts are not declared. So later 
 generated code does not have the benefit of knowledge of 
 asserted truth conditions in release mode. So in release mode, 
 without these truth conditions being established, the code 
 generated (apart from the asserts’ code) can be _worse than in 
 debug mode_, which seems bizarre, but it’s true.

 for example
     assert( x < 100 );
     …
     if ( x==200 )  // <— evaluates to false _at compile time_
          {
          // no code generated for this block in debug mode,
          // but is generated in release mode
          }
     …
     if ( x < 100 ) // <— no code generated for if-test as cond 
 == true at compile-time


This is by intention. While exceptions are used for resources 
like user input/file system/network,... you use asserts to 
validate your code.
When you publish your code to the world, the assertions have 
"done" their work and there is no need to include them in a 
release build.

Cases where you need asserts in release builds are an indicator, 
that you should have used exceptions instead.

Kind regards
Andre
Jul 15 2020
prev sibling next sibling parent reply 9il <ilyayaroshenko gmail.com> writes:
On Tuesday, 14 July 2020 at 21:58:49 UTC, Cecil Ward wrote:

 Does anyone know if this has already been published by someone 
 else?


https://github.com/libmir/mir-core/blob/master/source/mir/utility.d#L29

We test LDC and DMC. CI needs an update to be actually tested 
with GDC.
Jul 14 2020
parent Cecil Ward <cecil cecilward.com> writes:
On Wednesday, 15 July 2020 at 02:25:42 UTC, 9il wrote:

 On Tuesday, 14 July 2020 at 21:58:49 UTC, Cecil Ward wrote:

 Does anyone know if this has already been published by someone 
 else?


 https://github.com/libmir/mir-core/blob/master/source/mir/utility.d#L29

 We test LDC and DMC. CI needs an update to be actually tested 
 with GDC.


Brilliant. Many thanks.
Jul 15 2020
prev sibling parent Jacob Carlborg <doob me.com> writes:
On 2020-07-14 23:58, Cecil Ward wrote:

 What’s the best way to publish a D routine ?


As others have already said, on GitHub. Then as a Dub package as well [1].

[1] https://code.dlang.org

-- 
/Jacob Carlborg
Jul 15 2020