Prompt for files with given extensions

Prompt for files with given extensions

[Robin Neatherway]

I would like my function to prompt only for files with a given
extension. I have a source file, say foo.c, and would like to load the
corresponding test results file, say foo.results. However, if there
are multiple tests for foo.c, then they may have different filenames.

At the moment I use `read-file-name` with `foo.results` as a default,
but I would like to filter the possible completions by file extension.
Is this possible?

RE: Prompt for files with given extensions

[Drew Adams]

> I would like my function to prompt only for files with a given
> extension.

If you use Icicles, you can bind one of these variables in your
function, to control which file-name candidates are presented:

`icicle-file-match-regexp'
`icicle-file-no-match-regexp'
`icicle-file-predicate'

http://www.emacswiki.org/emacs/Icicles_-_Global_Filters#icicle-file-match-regexp

Re: Prompt for files with given extensions

[Michael Heerdegen]

Robin Neatherway <robin.neatherway@gmail.com> writes:

> At the moment I use `read-file-name` with `foo.results` as a default,
> but I would like to filter the possible completions by file extension.
> Is this possible?

You can just use the PREDICATE arg of `read-file-name' for that:

--8<---------------cut here---------------start------------->8---
;; -*- lexical-binding: t -*-

(defun my-filter-file-by-extension (extension)
  (lambda (file) (let ((file-extension (file-name-extension file)))
              (and (stringp file-extension)
                   (string= file-extension extension)))))

;; Use like this:
(read-file-name
 "File: " "~/" nil t nil
 (my-filter-file-by-extension "txt"))

--8<---------------cut here---------------end--------------->8---


Michael.

Re: Prompt for files with given extensions

[Robert Thorpe]

Robin Neatherway <robin.neatherway@gmail.com> writes:

> I would like my function to prompt only for files with a given
> extension. I have a source file, say foo.c, and would like to load the
> corresponding test results file, say foo.results. However, if there
> are multiple tests for foo.c, then they may have different filenames.
>
> At the moment I use `read-file-name` with `foo.results` as a default,
> but I would like to filter the possible completions by file extension.
> Is this possible?

Another possibility is to get the user to choose using a dired buffer.

E.g. (dired "~/foo/*.txt")

BR,
Robert Thorpe

Re: Prompt for files with given extensions

[Robin Neatherway]

Great, thanks a lot! I missed that option in the documentation.

On Wed, Feb 11, 2015 at 3:35 PM, Michael Heerdegen
<michael_heerdegen@web.de> wrote:
> Robin Neatherway <robin.neatherway@gmail.com> writes:
>
>> At the moment I use `read-file-name` with `foo.results` as a default,
>> but I would like to filter the possible completions by file extension.
>> Is this possible?
>
> You can just use the PREDICATE arg of `read-file-name' for that:
>
> --8<---------------cut here---------------start------------->8---
> ;; -*- lexical-binding: t -*-
>
> (defun my-filter-file-by-extension (extension)
>   (lambda (file) (let ((file-extension (file-name-extension file)))
>               (and (stringp file-extension)
>                    (string= file-extension extension)))))
>
> ;; Use like this:
> (read-file-name
>  "File: " "~/" nil t nil
>  (my-filter-file-by-extension "txt"))
>
> --8<---------------cut here---------------end--------------->8---
>
>
> Michael.
>
>