// The STRING-separator split, static (no island): empty pieces at the
// ends and between adjacent separators, multi-byte and multi-char
// separators, the whole-string separator, the empty separator's
// per-code-unit split, and results flowing into intrinsic array ops.
const csv = "a,b,,c,";
const parts = csv.split(",");
console.log(parts.length, JSON.stringify(parts));
console.log("aXbXc".split("X").join("-"), "aa".split("a").length);
console.log(JSON.stringify("banana".split("an")), JSON.stringify("banana".split("na")));
console.log(JSON.stringify("abc".split("abc")), JSON.stringify("abc".split("abcd")));
console.log(JSON.stringify("".split(",")), "".split(",").length);
console.log(JSON.stringify("".split("")), "".split("").length);
console.log("abc".split("").join("|"), "abc".split("").length);
// Unicode: multi-byte separators and pieces, per-unit split of BMP text.
console.log("α😀β😀γ".split("😀").join("+"), "α😀β😀γ".split("😀").length);
console.log("café société".split("é").join("<>"));
console.log("你好世界".split("").join(" "), "你好世界".split("").length);
console.log(JSON.stringify("日本語テスト".split("語")));
// Chains stay static: split → map/filter/indexOf/includes.
const words = "one two  three".split(" ");
console.log(words.length, words.indexOf("three"), words.includes("two"));
const nums = "1,2,3,4".split(",").map((s) => parseInt(s, 10) * 2);
console.log(nums.join(","));

// The optional limit is ToUint32'd, and truncation happens before wrap.
function limited(text: string, separator: string, limit: number): string {
  return JSON.stringify(text.split(separator, limit));
}
console.log(limited("a,b,,c,", ",", 0));
console.log(limited("a,b,,c,", ",", 1), limited("a,b,,c,", ",", 3));
console.log(limited("a,b,,c,", ",", 99), limited("a,b,,c,", ",", -1));
console.log(limited("a,b,,c,", ",", 2.9), limited("a,b,,c,", ",", 4294967298));
console.log(limited("a,b,,c,", ",", 4294967296), limited("a,b,,c,", ",", NaN));
console.log(limited("abcd", "", 2), limited("", ",", 1));

// Explicit and forwarded undefined are omission, with effects preserved.
let limitEffects = 0;
function undefinedLimit(): undefined {
  limitEffects++;
  return undefined;
}
function optionalLimit(limit?: number): string {
  return JSON.stringify("a,b,c".split(",", limit));
}
console.log(JSON.stringify("a,b,c".split(",", undefined)));
console.log(JSON.stringify("a,b,c".split(",", undefinedLimit())), limitEffects);
console.log(optionalLimit(), optionalLimit(undefined), optionalLimit(2));