Split a string only the at the first n occurrences of a delimiter

Question

I\'d like to split a string only the at the first n occurrences of a delimiter. I know, I could add them together using a loop, but isn\'t there a more straight forward appr

Answer 1

Yet another implementation with limit;

// takes string input only
function split(input, separator, limit) {
    input = input.split(separator);
    if (limit) {
        input = input.slice(0, limit - 1).concat(input.slice(limit - 1).join(separator));
    }
    return input;
}

Answer 2

In my case this solves my problem:

const splitted = path.split('/')
const core = splittedPath.slice(0, 2)
const rest = splittedPath.slice(2).join('/')
const result = [...core, rest]

Answer 3

ES2015

const splitAndAppend = (str, delim, count) => {
    const arr = str.split(delim);
    return [...arr.splice(0, count), arr.join(delim)];
}

Complexity O(n).

Answer 4

In my case I was trying to parse git grep stdout. So I had a {filename}:{linenumber}:{context}. I don't like splitting and then joining. We should be able to parse the string one time. You could simply step through each letter and split on the first two colons. A quicker way to do it out of the box is by using the match method and regex.

Hence,

txt.match(/(.+):(\d+):(.*)/)

Works great

Answer 5

Improved version of a sane limit implementation with proper RegEx support:

function splitWithTail(value, separator, limit) {
    var pattern, startIndex, m, parts = [];

    if(!limit) {
        return value.split(separator);
    }

    if(separator instanceof RegExp) {
        pattern = new RegExp(separator.source, 'g' + (separator.ignoreCase ? 'i' : '') + (separator.multiline ? 'm' : ''));
    } else {
        pattern = new RegExp(separator.replace(/([.*+?^${}()|\[\]\/\\])/g, '\\$1'), 'g');
    }

    do {
        startIndex = pattern.lastIndex;
        if(m = pattern.exec(value)) {
            parts.push(value.substr(startIndex, m.index - startIndex));
        }
    } while(m && parts.length < limit - 1);
    parts.push(value.substr(pattern.lastIndex));

    return parts;
}

Usage example:

splitWithTail("foo, bar, baz", /,\s+/, 2); // -> ["foo", "bar, baz"]

Built for & tested in Chrome, Firefox, Safari, IE8+.

Answer 6

var result = [string.split(' ',1).toString(), string.split(' ').slice(1).join(' ')];

Results in:

["Split", "this, but not this"]