Daily Challenge #131 - Remove Anchor from URL

Complete the function/method so that it returns the URL with anything after the anchor (#) removed.

Examples

# returns 'www.codewars.com'
remove_url_anchor('www.codewars.com#about')

# returns 'www.codewars.com?page=1'
remove_url_anchor('www.codewars.com?page=1')

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This challenge comes from jhoffner on CodeWars. Thank you to CodeWars, who has licensed redistribution of this challenge under the 2-Clause BSD License!

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Comments

[Amin]

JavaScript

Recursive solution with runtime type checking.

function removeUrlAnchor(url) {
    if (arguments.length !== 1) {
        throw new Error("expected exactly one argument");
    }

    if (typeof url !== "string") {
        throw new TypeError("expect first argument to be a string");
    }

    if (url.length === 0) {
        return "";
    }

    const [character, ...remainingUrl] = url;

    if (character === "#") {
        return "";
    }

    return character + removeUrlAnchor(remainingUrl.join(""));
}

Try it.

[Amin]

I just did several modifications to the algorithm to find the fastest solution in JavaScript using JSPerf. Turns out, the fastest way to get this done is by doing this:

function removeUrlAnchor(url) {
    const index = url.indexOf("#");

    return index === -1 ? url : url.slice(0, index);
}

I also removed the runtime type checking for the tests.

Tests are available here (tested in Chromium only).

[Josh]

How fast is my implementation?

[Amin]

Hi Josh. You could use JSPerf to test your code. It is really simple to get up and running your own benchmarks.

[Josh]

const unAnchor = (url) => url.split("#")[0]