Hello. I prepared a utility/library to output ANSI escape codes for terminal text attributes with capabilities as advertised at https://sites.google.com/site/jamadagni/files/temp/textattr-usage.html. (AFAIK this set of capabilities does not exist already in any existing package.)

This was first written in D and ported with much effort to C. This is the utility/library I refer to at http://forum.dlang.org/post/n6362a$1t7u$1@digitalmars.com.

Now I would prefer to keep the single C source and just write a thin D wrapper to call the C library because C is also callable from many other languages (and people can write wrappers for their favourite one).

However the only disadvantage (as discussed in the above thread) is that the C library function is not CTFE-able in D and thus I cannot write a D template in the wrapper to evaluate the colour codes at compile time.

On the other hand, I am not sure whether it is really useful to evaluate colour codes at compile time because it is tantamount to hardcoding them, and this means that any program using the library is not able to switch off colour output at will if stdout is not connected to a terminal.

If the library is only called at runtime, I am able to add a boolean switch to just make the library always output an empty string for all calls effectively switching off colour code output which is useful when stdout is not a terminal.

My question: do people agree that there is not much point in enabling CTFE of colour codes?

On Saturday, 14 October 2017 at 14:35:53 UTC, Shriramana Sharma wrote:
> Hello. I prepared a utility/library to output ANSI escape codes for terminal text attributes with capabilities as advertised at https://sites.google.com/site/jamadagni/files/temp/textattr-usage.html. (AFAIK this set of capabilities does not exist already in any existing package.)

My terminal.d works with most that stuff.

> My question: do people agree that there is not much point in enabling CTFE of colour codes?

I think it is worthless - color output must be a runtime decision to handle non-terminals or even terminals that don't support color output.

On Saturday, 14 October 2017 at 14:35:53 UTC, Shriramana Sharma wrote:
> Hello. I prepared a utility/library to output ANSI escape codes for terminal text attributes with capabilities as advertised at https://sites.google.com/site/jamadagni/files/temp/textattr-usage.html. (AFAIK this set of capabilities does not exist already in any existing package.)
>
> This was first written in D and ported with much effort to C. This is the utility/library I refer to at http://forum.dlang.org/post/n6362a$1t7u$1@digitalmars.com.
>
> Now I would prefer to keep the single C source and just write a thin D wrapper to call the C library because C is also callable from many other languages (and people can write wrappers for their favourite one).
>
> However the only disadvantage (as discussed in the above thread) is that the C library function is not CTFE-able in D and thus I cannot write a D template in the wrapper to evaluate the colour codes at compile time.
>
> On the other hand, I am not sure whether it is really useful to evaluate colour codes at compile time because it is tantamount to hardcoding them, and this means that any program using the library is not able to switch off colour output at will if stdout is not connected to a terminal.
>
> If the library is only called at runtime, I am able to add a boolean switch to just make the library always output an empty string for all calls effectively switching off colour code output which is useful when stdout is not a terminal.
>
> My question: do people agree that there is not much point in enabling CTFE of colour codes?

Why not simply add extern (C) wrappers for your D code? I see no point of using C, unless you want to be portable to arcane architectures.
With this approach you'll have both the portability of C and the advantages of using D.

On Saturday, 14 October 2017 at 14:51:12 UTC, Adam D. Ruppe wrote:
> My terminal.d works with most that stuff.

Yes I did look into existing solutions. Mainly my desire was not to work in D alone but something available at command line and as a library for shell-scripts and other languages too.

> I think it is worthless - color output must be a runtime decision to handle non-terminals or even terminals that don't support color output.

Thank you for that most candid reply!

On Saturday, 14 October 2017 at 17:17:41 UTC, Petar Kirov [ZombineDev] wrote:
> Why not simply add extern (C) wrappers for your D code? I see no point of using C, unless you want to be portable to arcane architectures.
> With this approach you'll have both the portability of C and the advantages of using D.

Yes I admit this idea hadn't occurred to me earlier.