Set parameters for a query

[jaapandre]

When using parameters for a query it would be usefull if we could tell pash to set the parameters, for instance set ${type} for query below, but of course multiple parameters would be necessary.
SELECT NON EMPTY {[Measures].[Sum]} ON COLUMNS, {LastPeriods(15, CurrentDateMember([Date], '["Date.Year_month"]\.[yyyy-mm]') )} ON ROWS FROM [SomeCube] WHERE {[ype.Name].[${type}]}

[rpbouman]

Nice new feature. To implement this I think I should rely on simple text-based substiturion (i.e. macro's).
In addition, we need a new SET command, something like

SET VARIABLE type = 'value';

And

SET VARIABLE type = null

to unset a variable.

Would be nice to make it so that if a variable is not SET prior to executing the query, user should be prompted to enter a value.