import { strict as assert } from "assert";

import {
  matchLeftIncl,
  matchRightIncl,
  matchLeft,
  matchRight,
} from "string-match-left-right";

// 3rd character is "d" because indexes start from zero.
// We're checking the string to the left of it, "bcd", inclusive of current character ("d").
// This means, "bcd" has to end with existing character and the other chars to the left
// must match exactly:
assert.equal(matchLeftIncl("abcdefghi", 3, ["bcd"]), "bcd");

// neither "ab" nor "zz" are to the left of 3rd index, "d":
assert.equal(matchLeft("abcdefghi", 3, ["ab", `zz`]), false);

// "def" is to the right of 3rd index (including it), "d":
assert.equal(matchRightIncl("abcdefghi", 3, ["def", `zzz`]), "def");

// One of values, "ef" is exactly to the right of 3rd index, "d":
assert.equal(matchRight("abcdefghi", 3, ["ef", `zz`]), "ef");

import { strict as assert } from "assert";

import {
  matchLeftIncl,
  matchRightIncl,
  matchLeft,
  matchRight,
} from "string-match-left-right";

// imagine you looped the string and wanted to catch where does attribute "class" start
// and end (not to mention to ensure that it's a real attribute, not something ending with this
// string "class").
// You catch "=", an index number 8.
// This library can check, is "class" to the left of it and feed what's to the left of it
// to your supplied callback function, which happens to be a checker "is it a space":
function isSpace(char) {
  return typeof char === "string" && char.trim() === "";
}

assert.equal(
  matchLeft('<a class="something">', 8, "class", { cb: isSpace }),
  "class"
);