Looking for an accurate solution:
function megasplit(toSplit, splitters) {
var splitters = splitters.sorted(function(a,b) {return b.length-a.length});
// sort by length; added here for better readability, easy 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) { // call recursively on segments
return megasplit(segment, splitters.slice(1))
})
.intersperse(token) // re-insert token
.flatten() // concatenate segments
.filter(Boolean);
}
}
Demonstration:
> megasplit(
"Go ye away, I want some peace && quiet. & Thanks.",
["Go ", ",", "&&", "&", "."]
)
["Go ", "ye away", ",", " I want some peace ", "&", "&", " quiet", ".", " ", "&", " Thanks", "."]
Reusable Machinery:
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)
}
Important Notes:
- This task required considerable research to accomplish elegantly:
- (Deep) copying an array using jQuery
- What is the most efficient way to concatenate N arrays in JavaScript? (developed my own method)
- How can I split text on commas not within double quotes, while keeping the quotes? (created my own method)
- The complexity increased as tokens were required to remain intact within the string and not be split (resulting in
"&", "&"). This necessitated recursion over using reduce.
- My personal preference would include empty strings with splits. While avoiding recursive splitting on the tokens, I would simplify the function to make the output mimic a standard
.split like ["", "Go ", "ye away", ",", " I want some peace ", "&&", " quiet", ".", " ", "&", " Thanks", ".", ""]
- It is worth noting that, if there's flexibility in requirements, the code could be condensed from a 15/20-liner to a 1/3-liner:
1-line solution following canonical splitting behavior:
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-line solution for readability:
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;
}