To understand how this all works, we have to take a brief dive into the parser combinator implementation.

为了理解其中的原理，我们必须简要了解解析器组合子的实现。

youdao

In the original parser, expressions like "5 + 5 + 5" were acceptable owing to the rep combinator in the grammar definition for expressions (expr) and terms (term).

在原来的解析器中，可以接受像“5 + 5 + 5”这样的表达式，因为语法中为表达式(expr)和术语(term)定义了rep组合子。

youdao

In the original parser, expressions like "5 + 5 + 5" were acceptable owing to the rep combinator in the grammar definition for expressions (expr) and terms (term).

在原来的解析器中，可以接受像“5 + 5 + 5”这样的表达式，因为语法中为表达式(expr)和术语(term)定义了rep组合子。

youdao