Procedures with keyword arguments (almost SRFI-89)

[Dominik Pantůček]

Hello CHICKEN users,

I've implemented a proof-of-concept SRFI-89-like define* and lambda* 
forms for CHICKEN. I thought I am aiming at SRFI-89 but in reality 
(given my heavy Racket background) I accidentally implemented 
Racket-style keyword arguments. Changing it to SRFI-89 is just a matter 
of two little tweaks to the syntax patterns.

The implementation can be found here:

https://gitlab.com/racketeer/chicken-racket-kwargs

The repository contains just the module and a README file with example 
usage - including error reporting. Apart from the last error reported, 
which is pretty generic (and my plan is to report something more 
meaningful there as well), syntax errors are properly reported during 
expansion time, procedure usage errors - of course - in run time.

A few questions:

1) Do you think this would be useful for other CHICKEN users and 
therefore an egg should be created for this eventually?

2) Do you prefer the Racket-style or SRFI-89 variant? (I can roll out 
both versions without any hassle).

3) I know it is not very efficient as the only CHICKEN-specific part is 
the if-keyword? syntax (which I tried to implement using various 
syntax-rules tricks, but ended up implementing a rather simple IR 
macro). In my opinion it does not matter as I am using it only for 
"large" procedures and the cost of setting up the bindings is negligible 
to the procedure body. Do you see any possible straightforward 
efficiency improvements? Do you think it matters more than I think?

Of course any other suggestions/opinions are more than welcome.

I am using CHICKEN for one little side project and this is part of this 
project - I just thought it might be useful to split it out and make it 
into a reusable module.


Cheers,
Dominik