Re: [henshin-dev] Injective Matching & Multi Nodes

[Christian Krause <henshin.ck@xxxxxxxxx>]

Hi Sebastian,

2014-10-14 18:47 GMT+02:00 Gabmeyer Sebastian <gabmeyer@xxxxxxxxxxxxxxxx>:

Sorry last mail went off too fast... Here the complete one.

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So this essentially means that any node of the host graph matched by the LHS graph cannot be matched again by a NAC/PAC node, right?

Well, it is implicitly matched already by the LHS and, yes, it won't be matched again to any other node.

 

I see, I think the way I'm using multi nodes would probably qualify as abuse ;)  since we only use simple rules in our application scenario, that is, no units and no control flow, we add multi-nodes to rules to match zero or more nodes. Since we do not have a kernel rule, only deletion nodes seem to make sense in our context... Is there any problem using multi nodes as described here?

Using multi-rules for applying a rule to all possible matches is a very common use case. Technically, you still have a kernel rule, but it is empty. The interpreter actually works in the same way as in the non-empty case. It first tries to find a match for the kernel rule and then matches the multi-rules as often as possible. The match of the kernel-rule in this case is the empty match.

Cheers,

Christian