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From: "Linus Björnstam" <linus.internet@fastmail.se>
To: "Mortimer Cladwell" <mbcladwell@gmail.com>, guile-user@gnu.org
Subject: Re: Meaning of <=> in the context of procedures
Date: Wed, 02 Jun 2021 18:21:39 +0200	[thread overview]
Message-ID: <5cee767e-f4a2-4dd9-ad96-203d9feba55b@www.fastmail.com> (raw)
In-Reply-To: <94db6b16-39d5-49ea-bc0a-f88f285fb4d9@www.fastmail.com>

To reply to myself: it is an exported identifier that is used in a define-json-mapping. It is good form for macros to export all its auxiliary syntax. 


-- 
  Linus Björnstam

On Wed, 2 Jun 2021, at 18:12, Linus Björnstam wrote:
> It is a trick to allow using the symbol '<=> as an identifier instead 
> of quoting it. Nothing special. Guile-json probably uses it somehow.
> 
> If it is used as auxiliary syntax in a macro, it is probably exported 
> so guile can warn that it is being shadowed instead of (or rather: in 
> addition to) producing bad error messages.
> 
> -- 
>   Linus Björnstam
> 
> On Wed, 2 Jun 2021, at 16:06, Mortimer Cladwell wrote:
> > Hi,
> > What does <=> mean/do?
> > It can be found in guile-json in the (json record) module, line 33:
> > 
> > 33 #:export (<=> define-json-mapping define-json-type))
> > 
> > Not mentioned in the entire Guile manual. Happens to be defined on line 36
> > of the module:
> > 
> > 36  (define <=> '<=>)
> > 
> > I didn't find that very helpful :)
> > Thanks
> > Mortimer
> > 
> 
> 



  reply	other threads:[~2021-06-02 16:21 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-02 14:06 Meaning of <=> in the context of procedures Mortimer Cladwell
2021-06-02 16:12 ` Linus Björnstam
2021-06-02 16:21   ` Linus Björnstam [this message]
2021-08-04 11:55 ` Ludovic Courtès

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