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From: jgart <jgart@dismail.de>
To: Guix Help <help-guix@gnu.org>
Subject: Why do we force the lazy python?
Date: Sat, 9 Jul 2022 20:51:06 -0500	[thread overview]
Message-ID: <20220709205106.GB24308@gac> (raw)


Hi Guixers,

Why do we check if python is a promise and then "force" it?

I'm just trying to understand the thinking for doing that since I didn't
write this code.

```
(let ((python (if (promise? python)
                  (force python)
                  python)))
     ...
```

I understand that force makes a promise evaluate (laziness). That's
about as much as I know.

guix/build-system/python.scm:119

all best,

jgart


             reply	other threads:[~2022-07-10  1:51 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-07-10  1:51 jgart [this message]
2022-07-10  8:04 ` Why do we force the lazy python? Ricardo Wurmus

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