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Re: Property values for boolean properties.

From: Talden <talden_at_gmail.com>
Date: 2007-06-18 06:21:53 CEST

"true" and "false" are literals in several programming languages (including
scripting) and could possibly be considered familiar enough to transcend
differences in spoken language. Of course I barely speak one language let
alone several so perhaps someone for whom English is not their first
language should comment.

Do "+" and "-" better avoid the language issue? Are people of other spoken
languages familiar enough with the include/exclude connotations of these
symbols.

Beyond these I think you are possibly stuck with the status quo of presence
and non-presence as being the next best thing.

I have to agree though that setting it to "off", "false" or "no" and having
it be interpreted as "on" is a bug not a feature.

--
Talden
On 6/18/07, Karl Fogel <kfogel@red-bean.com> wrote:
>
> Subversion has two versioned properties interpreted as booleans --
> 'svn:executable' and 'svn:needs-lock'.  (I'm ignoring 'svn:special'
> here, since users don't touch it directly.)
>
> Their property values are always normalized to "*", no matter what
> value you actually gave.  Thus:
>
>    $ svn propset svn:needs-lock "StrawberryFieldsForever" artwork.jpg
>    $ svn proplist -v artwork.jpg
>    Properties on 'artwork.jpg':
>      svn:needs-lock : *
>    $
>
> This presents users with the conundrum of what property value to use.
> Since you can use anything and it won't matter, what *should* you use?
> In practice, we often seem to recommend the word "on", for example:
>
>    $ svn propset svn:executable ON somescript
>    property 'svn:executable' set on 'somescript'
>    (from http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.propset.html
> )
>
> But the problem is that the word "off" doesn't turn the property off;
> instead, "off" turns it on too!  You have to use 'svn propdel' to turn
> the property off.
>
> I'm not sure what we can do about this.  Obviously, "off" doesn't mean
> "off" in all languages, and we wouldn't normally want potentially
> scripted command-line client behaviors to depend on the locale.  On
> the other hand, "off" and "no" are widely-known English words, and the
> rest of the command-line client interface depends on English words.
> So we could have
>
>    svn propset on  artwork.jpg  -->  sets the property
>    svn propset yes artwork.jpg  -->  sets the property
>
>    svn propset off artwork.jpg  -->  deletes the property
>    svn propset no  artwork.jpg  -->  deletes the property
>
> ...with the second two being special cases.
>
> Yes, yes, I realize that's lame.  Thoughts?  Creative solutions?
> Should we just live with it, and try to find another word besides
> "on" to use in our examples?
>
> -Karl
>
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Received on Mon Jun 18 06:21:57 2007

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