Re: [YANG] 7.6, default value for a type

Martin Bjorklund <mbj@tail-f.com> Sun, 13 January 2008 21:39 UTC

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Date: Sun, 13 Jan 2008 22:38:52 +0100 (CET)
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To: andy@andybierman.com
Subject: Re: [YANG] 7.6, default value for a type
From: Martin Bjorklund <mbj@tail-f.com>
In-Reply-To: <47880961.1030506@andybierman.com>
References: <47880961.1030506@andybierman.com>
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Andy Bierman <andy@andybierman.com> wrote:
> Hi,
> 
> Sec 7.6, para 5 says:
> 
>     If a leaf has a "default" statement, the leaf's default value is set
>     to the value of the "default" statement.  Otherwise, if the leaf's
>     type has a default value, and the leaf is not mandatory, then the
>     leaf's default value is set to the type's default value.  In all
>     other cases, the leaf does not have a default value.
> 
> The default value for each builtin type is not defined anywhere.

This is supposed to be a feature, not a bug.  If every type has a
default, you will never be able to define optional leafs.

> This is a nice detail, and covers things like the agent creating
> a bunch of counter objects or ifOperStatus objects.

Yes.  Define ifOperStatus with a default, or use a type with a
default.


/martin


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