Using of nonterminals with same name in rule

问题

How can I use as reciever two nonterminals with same name? For example, a have this rule:

expression returns [int value] : 'min' factor factor { 
    $expression.value = min($factor1.value, $factor2.value) //here
}

I need to get value from both factors, but they names are the same. So, if I write $factor.value twice, I get value of first factor.

回答1:

I think that it is solution for your problem:

expression returns [int value] : 'min' f1=factor f2=factor { 
    $expression.value = min($f1.value, $f2.value)
}

来源：https://stackoverflow.com/questions/59372023/using-of-nonterminals-with-same-name-in-rule