How to get the sub-rule's content in different parent-rule's action?

[shuizaiku7]

struct sub-rule : ... {};
struct p-rule1 : rule(sub-rule) {};
struct p-rule2 : rule(sub-rule) {};

p-rule1 and p-rule2 will use sub-rule,
In p-rule's action, I wanna get the content for sub-rule,
for now i can think of 3 ways:
01.unique name
assign a unique name to every sub-rule, and implement different action

02.temp variable
just store the content in a temp variable in state
and in p-rule's action, just use the temp variable

03.sub string
just get the sub-rule's content from the p-rule's content by substring it

But these 3 ways are not elegant,
Is there any better way to address this problem?

[ColinH]

There are more ways to do this, but not necessarily any better ones (you could set up a control to change the action depending on the parent rule). Depending on what is more fitting I have used all three of the options you gave, probably in the order you listed them. Sometimes it's also possible to change the grammar in a way that makes the problem disappear, but that is not always the best choice and sometimes not really possible at all.