野牛:$变量($ 1 $ 2等)如何与非令牌一起使用? [英] Bison: How $ variables ($1 $2 etc) work with non-tokens?

问题描述

我想知道$变量如何与非令牌(如代码块)一起使用.我的问题可以简化为:

I'm wondering how $ variables work with non-tokens, like blocks of code. And my question can be reduced to this:

我有这样一条规则，中间有一段代码.在这种情况下，$ 3和$ 4是谁?

I have a rule like this, with a block of code in the middle of it. In this case who is $3 and $4?

func-header: ret-type ID { strcpy(func_id,current_id); } LPAREN params RPAREN

推荐答案

在显示的规则中:

• ret-type是$1.
• ID是$2.
• 代码块为$3.
• LPAREN是$4.
• params是$5.
• RPAREN是$6.

• ret-type is $1.
• ID is $2.
• The code block is $3.
• LPAREN is $4.
• params is $5.
• RPAREN is $6.

换句话说，代码块充当非终端.

In other words, code blocks act as non-terminals.

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