[tkrn]

I'm not too fond of adding extra syntax or infix operators to Lisps but I have been thinking lately if maybe some limited form of infix macros could be useful, mainly in binding forms and such. E.g anaphoric ifs were a thing in the past for binding conditional expression's value; currently the preferred method seems to be if-let, or when-let and maybe unless-let too, and of course also the let* variants. And for completeness one might also need cond-let with its own different semantics. Oh, and maybe letrec and a few others too. But at that point it might make sense to come up with some kind of define-let-form macro facility to deal with the general pattern.

But all that gives me a nagging feeling that maybe traditional Lisp macros don't really compose that well? So as a band-aid I had the idea to introduce special infix macros so one could for example do "(if (expr as: var) (something-something var))", or maybe "(something-something var where: var expr)" and so on. I'm not sure what the exact semantics should be though, especially with the as: form. It's probably just a result of doing too much Smalltalk lately, but out of all the "let's fix lisp's syntax" ideas I don't think I have seen exactly this one before, so that's something I guess. (As an alternative we could also of course just replace the lambda form with something less verbose so one could "(if expr [var | something-something var])" and then make the conditionals regular functions, or even generic ones specialized on booleans. Or maybe I'll just get back to hacking my init.el for now and try to cleanse my mind of these impure thoughts.)

[shakna]

SRFI-105 is an infix syntax that composes well, and is supported by most Schemes.

Its enabled by default with Guile, for example.

    (+ 1 2 {10 * 2} 6)

https://srfi.schemers.org/srfi-105/