froebel/prefix.mjs

TypeScript utility library

import { capitalize } from "./case.mjs";

/**
 * Returns `str` prefixed with `prefix`. Optionally, allows prefxing in camel
 * case, i.e. `prefix('foo', 'bar', 'camel') => 'fooBar'`, or snake case, i.e.
 * `prefix('foo', 'bar', 'snake') => 'foo_bar'`.
 *
 * The result is strictly typed, so `prefix('foo', 'bar')` will return the type
 * `'foobar'`, not just a generic `string`.
 */
const prefix = (prefix, str, caseMod) => `${prefix}${caseMod === "snake" ? "_" : ""}${caseMod === "camel" ? capitalize(str) : str}`;

export default prefix;