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From: "Mr. Herr" <misterherr@freenet.de>
To: Caml List <caml-list@inria.fr>
Subject: [Caml-list] what does let () = ... define?
Date: Fri, 18 Mar 2016 19:04:08 +0100	[thread overview]
Message-ID: <56EC4318.2020701@freenet.de> (raw)

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Hi,

in a small presentation of OCaml (Linux User Group Bremen) I got some interesting
questions, and
trying to answer I noticed I took something for granted that was not fully understood.

Looking at this in the toplevel:

# let () = () ;;
# () ;;
- : unit = ()
# let _ = () ;;
- : unit = ()
# let None = None;;
Warning 8: this pattern-matching is not exhaustive.
Here is an example of a value that is not matched:
Some _
#

... the question is: okay, pattern matching left of the equal sign, but what does it
define?
It defines unit and None in the environment, and then that value is just sitting there?

/Str.

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             reply	other threads:[~2016-03-18 18:06 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-03-18 18:04 Mr. Herr [this message]
2016-03-18 18:26 ` Nick Lucaroni
2016-03-18 18:52 ` Christoph Höger
2016-03-18 22:06   ` Nicolas Barnier
2016-03-18 19:00 ` octachron
2016-03-18 19:42 ` Stefan Monnier
2016-03-18 21:29 ` Raphaël Proust
2016-03-18 21:54   ` Mr. Herr

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