Peg左递归删除

【问题标题】：Peg left recursion removingPeg左递归删除
【发布时间】：2014-08-24 08:52:43
【问题描述】：

我有这个 pegjs 语法。如何删除左递归？

atom   = term
    /  "^"
    /  "_"
    /  "\\"
    /  atom "."
    /  atom "." label
    /  atom ".(" labels ")"
term = [a-zA-Z0-9]+
labels = label ("|" label)*
label  = ("+" / "-")* [A-Za-z0-9]+

【问题讨论】：

标签： peg pegjs

【解决方案1】：

应该是这样的……

atomStatement =  atom "." /  atom "." label /  atom ".(" labels ")" / atom

atom   = term
/  "^"
/  "_"
/  "\\"

term = [a-zA-Z0-9]+
labels = label ("|" label)*
label  = ("+" / "-")* [A-Za-z0-9]+

【讨论】：