Re: Threading / Pipe Macro (Chris Vine, Mark H Weaver)

[Linus Björnstam]

Sorry, I didn't see that macro. I was referring to my macro that Erik linked to 
[1], which is a syntax rules macro that also allows for <> argument 
placeholders:

(~> 1 1+ (/ 10 <>) iota (+ <...>)) => 10

It defaults to left insert, so

(~> 10 (/ 2)) => 5

but also (like the syntax rules macro i posted) also supports functions without 
parents as you can see in the first example.

That's what I get for trying to.follow the discussion in an unthreaded mobile 
app :)

[1]: https://bitbucket.org/bjoli/guile-threading-macros/src/default/

-- 
  Linus Björnstam

On Tue, 9 Jul 2019, at 11:26, Chris Vine wrote:
> On Tue, 09 Jul 2019 08:01:01 +0200
> Linus Björnstam <address@hidden> wrote:
> > On Tue, 9 Jul 2019, at 01:02, Chris Vine wrote:
> > > On Mon, 8 Jul 2019 23:10:28 +0200t
> > > Zelphir Kaltstahl <address@hidden> wrote:
> > > > Hello Chris and hello Mark,
> > > > 
> > > > Thank you both for posting your macros! This is really useful and I am
> > > > looking forward to using this in the next situation where there would be
> > > > deep nesting or where it seems appropriate in other ways.
> > > > 
> > > > To understand what is going on in the macro, I wrote a lot of explaining
> > > > comments and uploaded it in a new repository, where I intend to keep
> > > > macros I come across and explain them, if I can:
> > > > 
> > > > https://gitlab.com/ZelphirKaltstahl/guile-scheme-macros/blob/master/threading-pipe-macro/macro.scm
> > > 
> > > You are using the wrong macro, because the one you have chosen has been
> > > revealed to be unhygienic.  Either use the syntax-rules one (which is
> > > the simplest) or the revised syntax-case macro.
> > > 
> > The comparison is also not really fair. The syntax-rules macro is doing
> > a lot more. A simple syntax-rules macro just inserting everything in
> > the leftmost position would loo something like
> > 
> > (define-syntax ->
> >   (syntax-rules ()
> >     ((-> exp) exp)
> >     ((-> exp (proc args ...) rest ...) (-> (proc exp args ...) rest ...)
> >     ((-> exp proc rest ...) (-> (proc exp) rest ...))))
> > 
> > I wrote this here in the mail without testing, so no guarantees that
> > it would work. It is simple enough. I think it should work.
> 
> I am not sure what comparison you are referring to.  However, I was
> comparing Mark Weaver's syntax-rules macro with my revised syntax-case
> macro, both of which have the same end result, and suggesting that
> Zelphir should not use my original syntax-case macro (the one he has
> referenced in his gitlab repository).
> 
> You must be thinking of something else.
>