--- Begin Message ---
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Subject: |
warning about unused returned value from some ert shoulds |
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Date: |
Tue, 16 Jul 2013 16:17:05 -0400 |
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User-agent: |
Gnus (www.gnus.org), GNU Emacs (www.gnu.org/software/emacs/) |
Package: emacs
Version: 24.3
Severity: minor
Compiling a file with contents:
;; -*- lexical-binding: t; -*-
(require 'ert)
(require 'cl-lib)
(defvar foo-test 1)
(should foo-test)
(cl-assert foo-test)
results in a warning (for some reason, only when lexical-binding is t):
foo.el:5:1:Warning: value returned from (car value-94600) is unused
The warning is from the `should'. Obviously it is a bogus warning
because the whole point of the should is to test the return value.
The similar cl-assert does not trigger a warning, because internally
cl-assert is written differently.
This is the same issue as http://debbugs.gnu.org/10969, for what is now
cl-pop.
byte-optimize-form-code-walker has special handling for the standard
`pop' macro so as not to warn about unused return values from (pop foo).
It would be nice if there was a general way to get the same result for
arbitrary macros (sort of the opposite of side-effect-free?), but I
don't see how.
--- End Message ---
--- Begin Message ---
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Subject: |
Re: bug#14883: warning about unused returned value from some ert shoulds |
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Date: |
Wed, 04 Sep 2013 23:06:38 -0400 |
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User-agent: |
Gnus/5.13 (Gnus v5.13) Emacs/24.3.50 (gnu/linux) |
> Compiling a file with contents:
> ;; -*- lexical-binding: t; -*-
> (require 'ert)
> (require 'cl-lib)
> (defvar foo-test 1)
> (should foo-test)
> (cl-assert foo-test)
> results in a warning (for some reason, only when lexical-binding is t):
> foo.el:5:1:Warning: value returned from (car value-94600) is unused
This `car' came from the closure conversion. I believe it is now fixed
in the trunk. Thank you.
Stefan
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