parsing - 我如何在 Rebol 中解析这个？

Question

我将如何解析这个字符串

"a:foo[and it's cousin bar[are here]]"

进入此

"a:" "foo[" "and" "it's" "cousin" "bar[" "are" "here" "]" "]"

本质上，我希望完成三件事，提取赋值“a:”，提取部分“foo[”(包括嵌套部分)和结束部分“]”。我可以均匀地间隔它们并只进行简单的解析，但我不想这样做。

希望这是有道理的。任何帮助将不胜感激!

谢谢!

Answer 1

定义您的语言的元素，然后在匹配它们时收集它们:

parse-my-language: use [word assignment section section-end space][

    word: use [letters][
        letters: charset [#"a" - #"z" ".'"]
        [some letters]
    ]
    assignment: [word ":"]
    section: [word "["]
    section-end: "]"

    space: charset " "

    func [statement /local out element][
        out: copy []
        if parse/all statement [
            any [
                copy element [
                    assignment | section | section-end | word
                ] (append out element)
                | some space
            ]
        ][out]
    ]
]

probe parse-my-language "a:foo[and it's cousin bar[are here]]"

注意:我使用'use来隔离仅用于此目的的单词。