String

Lightweight namespace for string manipulation

API

Motivation

globalThis.String functions and methods are very useful but has the following drawbacks :

• Most functions are on the prototype
  • Since ESM, it creates a double syntax standard toDashCase(string) VS myString.toLowerCase()
  • String.prototype should never be extended
• Some legacy design decisions
  • indexOf, lastIndexOf returns -1 when not found

String namespace corrects these problems in a pragmatic way :

• Extendable : as an object String can be extends with a simple { ...String, myMethod() {} }
• Uniform : every String function has a string as first parameter
• Expressive : indexOf and lastIndexOf returns Option<Int>

Usage

import { String, Option, Int } from '@w5s/core';

const baseName = (path: string): Option<string> => {
  const positionOption = String.lastIndexOf(expression, '/'); // Option<Int>;
  const afterLastSlash = Option.match(positionOption, (position) => ({
    None: () => path, // unchanged when not found
    Some: (position) => String.slice(path, position + 1), // everything after the last slash
  });
  return afterLastSlash;
}

Coding Guide

astuce

Prefer String functions over globalThis.String

• At best String will provide polyfill / better performance / better type safety
• At worst String will call the native function

FAQ