的Javascript分割陣列

Question

我想寫一個自定義字符串劃分功能，這是難度比我本來期望。

基本上，我通過在一個字符串，該字符串將分裂的值的陣列，並且它會返回子字符串數組，移除空的，並且包括它分裂上的值。如果字符串可以在同一個地方由兩個不同的值進行分割，較長的一個優先。

也就是說，

split("Go ye away, I want some peace && quiet. & Thanks.", ["Go ", ",", "&&", "&", "."]); 

應該返回

["Go ", "ye away", ",", " I want some peace ", "&&", " quiet", ".", " ", "&", " Thanks", "."] 

你能想到一個相當簡單的算法，這個的？如果有一個內置的方式在Javascript做到這一點（我不認爲有），這將是更好的。

Answer 1

喜歡的東西this？

function mySplit(input, delimiters) { 

    // Sort delimiters array by length to avoid ambiguity 
    delimiters.sort(function(a, b) { 
     if (a.length > b.length) { return -1; } 
     return 0; 
    } 

    var result = []; 

    // Examine input one character at a time 
    for (var i = 0; i < input.length; i++) { 
     for (var j = 0; j < delimiters.length; j++) { 
      if (input.substr(i, delimiters[j].length) == delimiters[j]) { 

       // Add first chunk of input to result 
       if (i > 0) { 
        result.push(input.substr(0, i)); 
       } 
       result.push(delimiters[j]); 

       // Reset input and iteration 
       input = input.substr(i + delimiters[j].length); 
       i = 0; 
       j = 0; 
      } 
     } 
    } 

    return result; 
} 

var input  = "Go ye away, I want some peace && quiet. & Thanks."; 
var delimiters = ["Go ", ",", "&&", "&", "."]; 

console.log(mySplit(input, delimiters)); 
// Output: ["Go ", "ye away", ",", " I want some peace ", 
//   "&&", " quiet", ".", " ", "&", " Thanks", "."] 

Answer 2

精確解問：

function megasplit(toSplit, splitters) { 
    var splitters = splitters.sorted(function(a,b) {return b.length-a.length}); 
                  // sort by length; put here for readability, trivial to separate rest of function into helper function 
    if (!splitters.length) 
     return toSplit; 
    else { 
     var token = splitters[0]; 
     return toSplit 
      .split(token)    // split on token 
      .map(function(segment) { // recurse on segments 
       return megasplit(segment, splitters.slice(1)) 
      }) 
      .intersperse(token)  // re-insert token 
      .flatten()    // rejoin segments 
      .filter(Boolean); 
    } 
} 

演示：

> megasplit(
     "Go ye away, I want some peace && quiet. & Thanks.", 
     ["Go ", ",", "&&", "&", "."] 
) 
["Go ", "ye away", ",", " I want some peace ", "&", "&", " quiet", ".", " ", "&", " Thanks", "."] 

機械（可重複使用！）：

Array.prototype.copy = function() { 
    return this.slice() 
} 
Array.prototype.sorted = function() { 
    var copy = this.copy(); 
    copy.sort.apply(copy, arguments); 
    return copy; 
} 
Array.prototype.flatten = function() { 
    return [].concat.apply([], this) 
} 
Array.prototype.mapFlatten = function() { 
    return this.map.apply(this,arguments).flatten() 
} 
Array.prototype.intersperse = function(token) { 
    // [1,2,3].intersperse('x') -> [1,'x',2,'x',3] 
    return this.mapFlatten(function(x){return [token,x]}).slice(1) 
} 

---

注：

• 這需要研究的一個體面的數額做優雅：
  • (Deep) copying an array using jQuery
  • What is the most efficient way to concatenate N arrays in JavaScript?（創建了自己的醜陋少法）
  • How can I split text on commas not within double quotes, while keeping the quotes? （垃圾的答案，再次創造了我自己的方法）
• 這由事實進一步複雜化要求令牌（雖然他們在字符串中被拋）不應該被分割（否則你會得到"&", "&"）的規範。這使得使用reduce不可能的，必要的遞歸。
• 我還親自不會忽視與分裂空字符串。我可以理解不想遞歸地分割令牌，但我個人簡化功能，並使輸出像正常.split和["", "Go ", "ye away", ",", " I want some peace ", "&&", " quiet", ".", " ", "&", " Thanks", ".", ""]
• 我應該指出，如果你願意放鬆你的要求一點，這正好從一個15/20-襯墊到三分之一襯裏：

---

如果一個跟隨典型分裂行爲1-襯墊：

Array.prototype.mapFlatten = function() { 
    ... 
} 
function megasplit(toSplit, splitters) { 
    return splitters.sorted(...).reduce(function(strings, token) { 
     return strings.mapFlatten(function(s){return s.split(token)}); 
    }, [toSplit]); 
} 

3內膽，如果上面是難以閱讀：

Array.prototype.mapFlatten = function() { 
    ... 
} 
function megasplit(toSplit, splitters) { 
    var strings = [toSplit]; 
    splitters.sorted(...).forEach(function(token) { 
     strings = strings.mapFlatten(function(s){return s.split(token)}); 
    }); 
    return strings; 
}