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Re: File search progress: database review and question on triggers


From: Pierre Neidhardt
Subject: Re: File search progress: database review and question on triggers
Date: Sun, 06 Sep 2020 12:05:26 +0200

Arun Isaac <arunisaac@systemreboot.net> writes:

> The function signature of search-file-package,
>
> --8<---------------cut here---------------start------------->8---
> (define (search-file-package pattern . more-patterns) ...)
> --8<---------------cut here---------------end--------------->8---
>
> can be rewritten as
>
> --8<---------------cut here---------------start------------->8---
> (define (search-file-package . patterns) ...)
> --8<---------------cut here---------------end--------------->8---
>
> No need to cons pattern onto more-patterns in the function body.

There is a subtle different: in the latter, (search-file-package) is
allowed and won't trigger a compile time error, while the former does.
This "foo . more-foo" paradigm is a way to say "1 or more arguments",
instead of "0 or more".

Cheers!

-- 
Pierre Neidhardt
https://ambrevar.xyz/

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