REBOL解析規則

這個偉大的工程（感謝蘇南達的建議How can I parse [a/b] ? syntax error in Rebol?）：REBOL解析規則

attribute: copy [] 
class: copy [] 
definition-rule: compose/deep [some [set class word! 'is 'defined 'by 
[some [copy attribute to (to-lit-word "/") thru (to-lit-word "/") ]] 
copy attribute to end]] 
parse [Customer is defined by First Name/Last Name/Email] definition-rule

，但我現在需要添加一些附加指令（追加輸出類），它不工作了：

attribute: copy [] 
class: copy [] 
definition-rule: compose/deep [some [set class word! (append output class) 'is 'defined 'by 
[some [copy attribute to (to-lit-word "/") thru (to-lit-word "/") ]] 
copy attribute to end]] 
parse [Customer is defined by First Name/Last Name/Email] definition-rule

來源

2009-09-22 Rebol Tutorial

好吧，讓我們看看是否再次回答Sunanda。我不太明白爲什麼一個教程提出問題，但我準備犯錯。 – 2009-09-22 04:56:02

我很樂意在任何有REBOL問題的論壇上回答有關REBOL的問題（如果我知道答案的話）。到目前爲止，REBOL社區對Stackoverflow的使用非常少 - 主要是RebolTutorial提出的問題，還有幾個人（主要是我到目前爲止）的迴應。如果這給任何人造成問題，那麼Reboltutorial可以切換到REBOL特定的論壇之一以獲得他/她的Q＆A支持。 – Sunanda 2009-09-22 13:57:59

的這裏的問題是，組成是吃所有表達式在括號中。你很高興它吃（以點亮的詞「/」），但是你認真不希望它吃（附加輸出類），因爲這是爲在解析方言。

有可能是一個聰明的做法，但這應該工作：刪除通過執行點燃字解析規則之外工作撰寫 ...

attribute: copy [] 
class: copy [] 
output: copy "" 
fs: to-lit-word "/" ;; define a forward slash lit-word 

definition-rule: [ 
    some [set class word! (append output class) 'is 'defined 'by [ 
     some [copy attribute to fs thru fs] 
    ] 
    copy attribute to end] 
    ] 

parse [Customer is defined by First Name/Last Name/Email] definition-rule 
== true

我不能完全肯定你正在嘗試使用此代碼做的，但你想在年底提取的屬性集，然後再考慮這種變化：

attribute: copy [] 
attributes: copy [] 
class: copy [] 
output: copy "" 
fs: to-lit-word "/" ;; define a forward slash lit-word 

definition-rule: [ 
    some [set class word! (append output class) 'is 'defined 'by [ 
     some [copy attribute to fs thru fs (append/only attributes attribute)] 
    ] 
    copy attribute to end (append/only attributes attribute)] 
    ] 

parse [Customer is defined by First Name/Last Name/Email] definition-rule 

print ["==" class mold attributes] 

== Customer [[First Name] [Last Name] [Email]]

來源

2009-09-22 14:12:54 Sunanda

非常感謝，我需要在第二個例子中這樣做的：屬性：複製[] 類：複製[] FS：要點亮的詞「/」輸出：複製「」定義規則：[ 一些[套課文！（追加輸出連接屬性「;」）] [ ] 複製屬性結束（追加輸出屬性）] [ ] 解析[客戶由名/姓/電子郵件定義] definition-rule 探針輸出 – 2009-09-22 20:02:46

我重新發布代碼註釋，因爲它是不可讀，W我想要做的正是這樣的帽子：

attribute: copy [] 
class: copy [] 
fs: to-lit-word "/" 
output: copy "" 


definition-rule: [ 
    some [set class word! (append output join class "|") 'is 'defined 'by [ 
     some [copy attribute to fs thru fs (append output join attribute ";")] 
    ] 
    copy attribute to end (append output attribute)] 
] 

parse [Customer is defined by First Name/Last Name/Email] definition-rule 
probe output

來源

2009-09-22 20:04:02

回答

相關問題