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nth-check

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Parses and compiles CSS nth-checks to highly optimized functions.

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import { compile, generate } from "./compile.js"; import { parse } from "./parse.js"; /** * Parses and compiles a formula to a highly optimized function. * Combination of {@link parse} and {@link compile}. * * If the formula doesn't match any elements, * it returns [`boolbase`](https://github.com/fb55/boolbase)'s `falseFunc`. * Otherwise, a function accepting an _index_ is returned, which returns * whether or not the passed _index_ matches the formula. * * Note: The nth-rule starts counting at `1`, the returned function at `0`. * @param formula The formula to compile. * @example * const check = nthCheck("2n+3"); * * check(0); // `false` * check(1); // `false` * check(2); // `true` * check(3); // `false` * check(4); // `true` * check(5); // `false` * check(6); // `true` */ export default function nthCheck(formula) { return compile(parse(formula)); } /** * Parses and compiles a formula to a generator that produces a sequence of indices. * Combination of {@link parse} and {@link generate}. * @param formula The formula to compile. * @returns A function that produces a sequence of indices. * @example <caption>Always increasing</caption> * * ```js * const gen = nthCheck.sequence('2n+3') * * gen() // `1` * gen() // `3` * gen() // `5` * gen() // `8` * gen() // `11` * ``` * @example <caption>With end value</caption> * * ```js * * const gen = nthCheck.sequence('-2n+5'); * * gen() // 0 * gen() // 2 * gen() // 4 * gen() // null * ``` */ export function sequence(formula) { return generate(parse(formula)); } export { compile, generate } from "./compile.js"; export { parse } from "./parse.js"; //# sourceMappingURL=index.js.map