How do I split a string, breaking at a particular character?

Question

I have this string

\'john smith~123 Street~Apt 4~New York~NY~12345\'

Using JavaScript, what is the fastest way to parse this into

Answer 1

This string.split("~")[0]; gets things done.

source: String.prototype.split()

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Another functional approach using curry and function composition.

So the first thing would be the split function. We want to make this "john smith~123 Street~Apt 4~New York~NY~12345" into this ["john smith", "123 Street", "Apt 4", "New York", "NY", "12345"]

const split = (separator) => (text) => text.split(separator);
const splitByTilde = split('~');

So now we can use our specialized splitByTilde function. Example:

splitByTilde("john smith~123 Street~Apt 4~New York~NY~12345") // ["john smith", "123 Street", "Apt 4", "New York", "NY", "12345"]

To get the first element we can use the list[0] operator. Let's build a first function:

const first = (list) => list[0];

The algorithm is: split by the colon and then get the first element of the given list. So we can compose those functions to build our final getName function. Building a compose function with reduce:

const compose = (...fns) => (value) => fns.reduceRight((acc, fn) => fn(acc), value);

And now using it to compose splitByTilde and first functions.

const getName = compose(first, splitByTilde);

let string = 'john smith~123 Street~Apt 4~New York~NY~12345';
getName(string); // "john smith"