str-indexes-of-plus^4.0.1

Like indexOf but returns array and counts per-grapheme

Install via npm

npm i str-indexes-of-plus

This package is ESM only: Node 12+ is needed to use it and it must be imported instead of required:

import { strIndexesOfPlus } from "str-indexes-of-plus";

If you need a legacy version which works with require, use version 3.1.0:

"str-indexes-of-plus": "3.1.0",

Install as a script, via CDN

Put this in your HTML:

<script src="https://cdn.jsdelivr.net/npm/str-indexes-of-plus/dist/str-indexes-of-plus.umd.js"></script>

Then, you’ll get a global variable strIndexesOfPlus in your Global object and you consume it like this:

const { strIndexesOfPlus } = strIndexesOfPlus;

Trivia

This program has 67 assertions in its unit tests. That's more than all unit test assertions' median (48) but less than geometric mean (70).

In monorepo, one other package, object-flatten-referencing, consumes this package.

Quick Take

import { strict as assert } from "assert";
import { strIndexesOfPlus } from "str-indexes-of-plus";

// searches for string in a string, returns array:
assert.deepEqual(
  strIndexesOfPlus("abc-abc-abc-abc", "abc"),
  [0, 4, 8, 12]
);

// all graphemes are counted as one, emoji too:
assert.deepEqual(
  strIndexesOfPlus("🐴-🦄", "🦄"),
  [2] // not [3] considering unicorn is 2-characters long
);

// you can offset the start of a search:
assert.deepEqual(
  strIndexesOfPlus("abczabc", "abc", 3),
  [4]
);

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Compared to Others

method / program	returns	index system based on
`String.prototype.indexOf()`	index where the first finding starts	code point count
`str-indexes-of`	array of indexes where each finding starts	code point count
📦 This package, `str-indexes-of-plus`	array of indexes where each finding starts	grapheme count

See this article about Unicode, graphemes and code points.

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API

strIndexesOfPlus(
  str,
  searchValue,
  [fromIndex]
)

In other words, it's a function which takes three arguments, third one is optional (marked by square brackets).

Output: an array of zero or more numbers, each indicating the index of each finding's first character. Unicode astral characters are counted, as one character-long.

Input argument	Type	Obligatory?	Description
`str`	string	yes	Source string, where to search.
`searchValue`	string	yes	What to search for.
`fromIndex`	natural number or zero	no	If set, the searching will start from this index.