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Carl Gamble

I have been trying to use the "collect" and "select" statements to generate a collection for use in an armani rule, but so far have not been able to produce a rule that type checks.

Below is a copy of the rule that so far I think has come closest.

acme · Site Admin Joined: 19 Jan 2006 Posts: 33

Carl

I'm having trouble parsing both the Acme and the English Smile

Maybe we could break this down somewhat.

1. select p in self.ports | satisfiesType (p, PTWSCU) gives you the set of ports in the component that satisfy PTWSCU. Let's call this <S> for now.

2. collect n : string in <S> | name != "". This is where I have trouble (BTW, port is a keyword and so you can't use it as a quantifier name). The problem is, where does name come from> Also, the declaration of n is not correct. Collect is used to collect substructure, and so the syntax of it should be something like:

collect Reference : TypeRef in SetReference | predicate

So, from the Armani LRM, you can say something like:

1. collect c.ports : set{port} in self.components | satisfiesType (c, Filter): This will form a set of set-of-ports of components that satisfy the Filter type in a system. So, the declaration c.ports both declares a variable c and then immediately references its substructure. So, c can be used in the predicate afterwards.

2. { collect v.x : int in { [x=4; y=6], [x=5; y=7]; [x=5; y=8] } | v.y – v.x = 2 }
This will return the set { 4, 5 }. Again, the type of v here will be a record [x: int; y : int] and so it can be used in the expression v.y - v.x = 2

Maybe you could clarify what it is you are trying to accomplish in simpler terms so that we can work it out.

OK, full disclosure here. I have just checked the parser and it seems that collect is not implemented. If you were to successfully get it to parse, it would throw and unsupported operation exception. We're looking at how this should be implemented now.