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From: Nicolas Richard <theonewiththeevillook@yahoo.fr>
To: Philipp Stephani <p.stephani2@gmail.com>
Cc: "help-gnu-emacs@gnu.org" <help-gnu-emacs@gnu.org>
Subject: Re: The two-argument form of defvar
Date: Thu, 19 Mar 2015 16:03:05 +0100	[thread overview]
Message-ID: <87vbhxf2s6.fsf@yahoo.fr> (raw)
In-Reply-To: <CAArVCkQUoK9tyx7t2nMmE5aJ5s++mUa9w9dpVwyFm3oZA4qsxQ@mail.gmail.com> (Philipp Stephani's message of "Thu, 19 Mar 2015 11:39:48 +0000")

Philipp Stephani <p.stephani2@gmail.com> writes:

> Hi,
>
> when looking at the source code of defvar it becomes clear that the
> two-argument form
>
> (defvar foo)
>
> is a no-op.

Not always a no-op. The source code has this comment :
    /* A simple (defvar foo) with lexical scoping does "nothing" except
       declare that var to be dynamically scoped *locally* (i.e. within
       the current file or let-block).  */

To reflect the above comment, the docstring has :
| The `defvar' form also declares the variable as "special",
| so that it is always dynamically bound even if `lexical-binding' is t.

-- 
Nicolas Richard



  reply	other threads:[~2015-03-19 15:03 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-19 11:39 The two-argument form of defvar Philipp Stephani
2015-03-19 15:03 ` Nicolas Richard [this message]
2015-03-19 15:52   ` Tassilo Horn
2015-04-18  9:25     ` Philipp Stephani
2015-04-18 13:27       ` Stefan Monnier
2015-04-18 14:14       ` Drew Adams
2015-04-18 16:50         ` Philipp Stephani
     [not found]       ` <mailman.1013.1429363810.904.help-gnu-emacs@gnu.org>
2015-04-19 21:48         ` Emanuel Berg

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