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Re: documents or examples on defining / adding a new syntax?

On Mon, 5 Aug 2013, Michael StrÃder wrote:

Zhang Weiwu wrote:
3. Do I need to design a new syntax at all? My requirement is the following:

    I need a new syntax for ranged-values. Examples are:

    - netWeight: 12~13kg
    - ISOSensitivity: 800~1600
    - heightAdjustableRange: 1.2m~1.5m

    The spec of ranged-value is a numeric, optionally followed by a
    measurement unit, followed by a tild as seperatorâ, followed by
    another measurement.

    The syntax needs its own comparison rules, so that you can filter a
    range, and get entries who offer values ranging in that range.

Not exactly what you're after but have a look at slapo-constraint. Maybe you
can find some suitable regex patterns for your use-case.

Hmm, it would be handy to have min/max constraints for attribute types for
which an ORDERING matching rule is defined. So maybe extending
slapo-constraint would be the most flexible way of implementing ranges.

Thanks for the comment, but the problem your solution to solve is not the one I face. I guess I wasn't clear enough.

I do not intend to constrain the value of attributes, but to store the constraint into the value.

Perhaps it is best explained with examples. Say I want to find out all desks that can adjust to exactly 1.4m, there are 3 entris:

dn: model=BigDesk,dc=wood,dc=com
model: BigDesk
heightAdjustableRange: 1.6m~2m

dn: model=MediumDesk,dc=wood,dc=com
model: MediumDesk
heightAdjustableRange: 1.3m~1.8m

dn: model=SmallDesk,dc=wood,dc=com
model: SmallDesk
heightAdjustableRange: 1.1m~1.5m

And I do an inquiry, expect to get only MediumDesk and SmallDesk.

To reprise, there is no constraint to the value, but there are constraints in the value.

There are 2 ways to solve it, I am unsure which is better. The first is to design a new SYNTAX, apparently requiring coding a matching model.

The other method is to use multi-value INTEGER syntax:

dn: model=BigDesk,dc=wood,dc=com
model: BigDesk
possibleHeightInCM: 160
possibleHeightInCM: 200

dn: model=MediumDesk,dc=wood,dc=com
model: MediumDesk
possibleHeightInCM: 130
possibleHeightInCM: 180

dn: model=SmallDesk,dc=wood,dc=com
model: SmallDesk
possibleHeightInCM: 110
possibleHeightInCM: 150

And I can find my choice of desk by using:


Which should result the SmallDesk and MediumDesk.