Searching

Queries that scan the view and return a primitive — no allocation. The needle for each can be a string or a str, so you can search a view inside a view.

These are the SWAR/SIMD-accelerated paths.

indexOf / lastIndexOf

indexOf(needle, start?) returns the first code-unit index at or after start, or -1. lastIndexOf(needle, start?) searches backward from start.

const v = str.from("the quick brown fox");
v.indexOf("brown"); // 10
v.indexOf("o", 12); // 17
v.indexOf("zzz"); // -1
v.lastIndexOf("o"); // 17

A str needle works identically:

const needle = str.slice("xxbrownyy", 2, 7); // "brown"
v.indexOf(needle); // 10

Semantics match native String exactly, including the quirks: an empty needle returns 0 for indexOf and the haystack length for lastIndexOf, and a negative start clamps to 0.

includes

includes(needle) — true if the needle occurs anywhere.

str.from("the quick brown fox").includes("quick"); // true
str.includes("the quick brown fox", "cat"); // false

startsWith / endsWith

startsWith(needle, start?) and endsWith(needle, end?) test a prefix/suffix at an optional position, matching String#startsWith / String#endsWith (including position clamping).

const v = str.from("the quick brown fox");
v.startsWith("the"); // true
v.startsWith("quick", 4); // true
v.endsWith("fox"); // true
v.endsWith("quick", 9); // true

charCodeAt / codePointAt

charCodeAt(i) returns the UTF-16 code unit at i (or -1 if out of range); codePointAt(i) decodes a surrogate pair into a full code point.

const v = str.from("a😀b");
v.charCodeAt(0); // 97
v.codePointAt(1); // 128512 (😀)

The [] operator is shorthand for charCodeAt.

length / isEmpty

const v = str.from("hello");
v.length; // 5
v.isEmpty; // false
str.length("hello"); // 5 (free-function form)