Lorem Ipsum MCP Server

/** * This module provides utility functions and type class instances for working with the `string` type in TypeScript. * It includes functions for basic string manipulation, as well as type class instances for * `Equivalence` and `Order`. * * @since 2.0.0 */ import type { NonEmptyArray } from "./Array.js" import * as equivalence from "./Equivalence.js" import { dual } from "./Function.js" import * as readonlyArray from "./internal/array.js" import * as number from "./Number.js" import * as Option from "./Option.js" import * as order from "./Order.js" import type * as Ordering from "./Ordering.js" import type { Refinement } from "./Predicate.js" import * as predicate from "./Predicate.js" /** * Tests if a value is a `string`. * * @example * ```ts * import * as assert from "node:assert" * import { String } from "effect" * * assert.deepStrictEqual(String.isString("a"), true) * assert.deepStrictEqual(String.isString(1), false) * ``` * * @category guards * @since 2.0.0 */ export const isString: Refinement<unknown, string> = predicate.isString /** * @category instances * @since 2.0.0 */ export const Equivalence: equivalence.Equivalence<string> = equivalence.string /** * @category instances * @since 2.0.0 */ export const Order: order.Order<string> = order.string /** * The empty string `""`. * * @since 2.0.0 */ export const empty: "" = "" as const /** * Concatenates two strings at the type level. * * @since 2.0.0 */ export type Concat<A extends string, B extends string> = `${A}${B}` /** * Concatenates two strings at runtime. * * @since 2.0.0 */ export const concat: { /** * Concatenates two strings at runtime. * * @since 2.0.0 */ <B extends string>(that: B): <A extends string>(self: A) => Concat<A, B> /** * Concatenates two strings at runtime. * * @since 2.0.0 */ <A extends string, B extends string>(self: A, that: B): Concat<A, B> } = dual(2, (self: string, that: string): string => self + that) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * assert.deepStrictEqual(pipe('a', String.toUpperCase), 'A') * ``` * * @since 2.0.0 */ export const toUpperCase = <S extends string>(self: S): Uppercase<S> => self.toUpperCase() as Uppercase<S> /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * assert.deepStrictEqual(pipe('A', String.toLowerCase), 'a') * ``` * * @since 2.0.0 */ export const toLowerCase = <T extends string>(self: T): Lowercase<T> => self.toLowerCase() as Lowercase<T> /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * assert.deepStrictEqual(pipe('abc', String.capitalize), 'Abc') * ``` * * @since 2.0.0 */ export const capitalize = <T extends string>(self: T): Capitalize<T> => { if (self.length === 0) return self as Capitalize<T> return (toUpperCase(self[0]) + self.slice(1)) as Capitalize<T> } /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * assert.deepStrictEqual(pipe('ABC', String.uncapitalize), 'aBC') * ``` * * @since 2.0.0 */ export const uncapitalize = <T extends string>(self: T): Uncapitalize<T> => { if (self.length === 0) return self as Uncapitalize<T> return (toLowerCase(self[0]) + self.slice(1)) as Uncapitalize<T> } /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * assert.deepStrictEqual(pipe('abc', String.replace('b', 'd')), 'adc') * ``` * * @since 2.0.0 */ export const replace = (searchValue: string | RegExp, replaceValue: string) => (self: string): string => self.replace(searchValue, replaceValue) /** * @since 2.0.0 */ export type Trim<A extends string> = TrimEnd<TrimStart<A>> /** * @example * ```ts * import * as assert from "node:assert" * import { String } from "effect" * * assert.deepStrictEqual(String.trim(' a '), 'a') * ``` * * @since 2.0.0 */ export const trim = <A extends string>(self: A): Trim<A> => self.trim() as Trim<A> /** * @since 2.0.0 */ export type TrimStart<A extends string> = A extends `${" " | "\n" | "\t" | "\r"}${infer B}` ? TrimStart<B> : A /** * @example * ```ts * import * as assert from "node:assert" * import { String } from "effect" * * assert.deepStrictEqual(String.trimStart(' a '), 'a ') * ``` * * @since 2.0.0 */ export const trimStart = <A extends string>(self: A): TrimStart<A> => self.trimStart() as TrimStart<A> /** * @since 2.0.0 */ export type TrimEnd<A extends string> = A extends `${infer B}${" " | "\n" | "\t" | "\r"}` ? TrimEnd<B> : A /** * @example * ```ts * import * as assert from "node:assert" * import { String } from "effect" * * assert.deepStrictEqual(String.trimEnd(' a '), ' a') * ``` * * @since 2.0.0 */ export const trimEnd = <A extends string>(self: A): TrimEnd<A> => self.trimEnd() as TrimEnd<A> /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * assert.deepStrictEqual(pipe('abcd', String.slice(1, 3)), 'bc') * ``` * * @since 2.0.0 */ export const slice = (start?: number, end?: number) => (self: string): string => self.slice(start, end) /** * Test whether a `string` is empty. * * @example * ```ts * import * as assert from "node:assert" * import { String } from "effect" * * assert.deepStrictEqual(String.isEmpty(''), true) * assert.deepStrictEqual(String.isEmpty('a'), false) * ``` * * @since 2.0.0 */ export const isEmpty = (self: string): self is "" => self.length === 0 /** * Test whether a `string` is non empty. * * @since 2.0.0 */ export const isNonEmpty = (self: string): boolean => self.length > 0 /** * Calculate the number of characters in a `string`. * * @example * ```ts * import * as assert from "node:assert" * import { String } from "effect" * * assert.deepStrictEqual(String.length('abc'), 3) * ``` * * @since 2.0.0 */ export const length = (self: string): number => self.length /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * assert.deepStrictEqual(pipe('abc', String.split('')), ['a', 'b', 'c']) * assert.deepStrictEqual(pipe('', String.split('')), ['']) * ``` * * @since 2.0.0 */ export const split: { /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * assert.deepStrictEqual(pipe('abc', String.split('')), ['a', 'b', 'c']) * assert.deepStrictEqual(pipe('', String.split('')), ['']) * ``` * * @since 2.0.0 */ (separator: string | RegExp): (self: string) => NonEmptyArray<string> /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * assert.deepStrictEqual(pipe('abc', String.split('')), ['a', 'b', 'c']) * assert.deepStrictEqual(pipe('', String.split('')), ['']) * ``` * * @since 2.0.0 */ (self: string, separator: string | RegExp): NonEmptyArray<string> } = dual(2, (self: string, separator: string | RegExp): NonEmptyArray<string> => { const out = self.split(separator) return readonlyArray.isNonEmptyArray(out) ? out : [self] }) /** * Returns `true` if `searchString` appears as a substring of `self`, at one or more positions that are * greater than or equal to `position`; otherwise, returns `false`. * * @since 2.0.0 */ export const includes = (searchString: string, position?: number) => (self: string): boolean => self.includes(searchString, position) /** * @since 2.0.0 */ export const startsWith = (searchString: string, position?: number) => (self: string): boolean => self.startsWith(searchString, position) /** * @since 2.0.0 */ export const endsWith = (searchString: string, position?: number) => (self: string): boolean => self.endsWith(searchString, position) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("abc", String.charCodeAt(1)), Option.some(98)) * assert.deepStrictEqual(pipe("abc", String.charCodeAt(4)), Option.none()) * ``` * * @since 2.0.0 */ export const charCodeAt: { /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("abc", String.charCodeAt(1)), Option.some(98)) * assert.deepStrictEqual(pipe("abc", String.charCodeAt(4)), Option.none()) * ``` * * @since 2.0.0 */ (index: number): (self: string) => Option.Option<number> /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("abc", String.charCodeAt(1)), Option.some(98)) * assert.deepStrictEqual(pipe("abc", String.charCodeAt(4)), Option.none()) * ``` * * @since 2.0.0 */ (self: string, index: number): Option.Option<number> } = dual( 2, (self: string, index: number): Option.Option<number> => Option.filter(Option.some(self.charCodeAt(index)), (charCode) => !isNaN(charCode)) ) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("abcd", String.substring(1)), "bcd") * assert.deepStrictEqual(pipe("abcd", String.substring(1, 3)), "bc") * ``` * * @since 2.0.0 */ export const substring = (start: number, end?: number) => (self: string): string => self.substring(start, end) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("abc", String.at(1)), Option.some("b")) * assert.deepStrictEqual(pipe("abc", String.at(4)), Option.none()) * ``` * * @since 2.0.0 */ export const at: { /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("abc", String.at(1)), Option.some("b")) * assert.deepStrictEqual(pipe("abc", String.at(4)), Option.none()) * ``` * * @since 2.0.0 */ (index: number): (self: string) => Option.Option<string> /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("abc", String.at(1)), Option.some("b")) * assert.deepStrictEqual(pipe("abc", String.at(4)), Option.none()) * ``` * * @since 2.0.0 */ (self: string, index: number): Option.Option<string> } = dual(2, (self: string, index: number): Option.Option<string> => Option.fromNullable(self.at(index))) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("abc", String.charAt(1)), Option.some("b")) * assert.deepStrictEqual(pipe("abc", String.charAt(4)), Option.none()) * ``` * * @since 2.0.0 */ export const charAt: { /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("abc", String.charAt(1)), Option.some("b")) * assert.deepStrictEqual(pipe("abc", String.charAt(4)), Option.none()) * ``` * * @since 2.0.0 */ (index: number): (self: string) => Option.Option<string> /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("abc", String.charAt(1)), Option.some("b")) * assert.deepStrictEqual(pipe("abc", String.charAt(4)), Option.none()) * ``` * * @since 2.0.0 */ (self: string, index: number): Option.Option<string> } = dual( 2, (self: string, index: number): Option.Option<string> => Option.filter(Option.some(self.charAt(index)), isNonEmpty) ) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("abc", String.codePointAt(1)), Option.some(98)) * ``` * * @since 2.0.0 */ export const codePointAt: { /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("abc", String.codePointAt(1)), Option.some(98)) * ``` * * @since 2.0.0 */ (index: number): (self: string) => Option.Option<number> /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("abc", String.codePointAt(1)), Option.some(98)) * ``` * * @since 2.0.0 */ (self: string, index: number): Option.Option<number> } = dual(2, (self: string, index: number): Option.Option<number> => Option.fromNullable(self.codePointAt(index))) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("abbbc", String.indexOf("b")), Option.some(1)) * ``` * * @since 2.0.0 */ export const indexOf = (searchString: string) => (self: string): Option.Option<number> => Option.filter(Option.some(self.indexOf(searchString)), number.greaterThanOrEqualTo(0)) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("abbbc", String.lastIndexOf("b")), Option.some(3)) * assert.deepStrictEqual(pipe("abbbc", String.lastIndexOf("d")), Option.none()) * ``` * * @since 2.0.0 */ export const lastIndexOf = (searchString: string) => (self: string): Option.Option<number> => Option.filter(Option.some(self.lastIndexOf(searchString)), number.greaterThanOrEqualTo(0)) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * assert.deepStrictEqual(pipe("a", String.localeCompare("b")), -1) * assert.deepStrictEqual(pipe("b", String.localeCompare("a")), 1) * assert.deepStrictEqual(pipe("a", String.localeCompare("a")), 0) * ``` * * @since 2.0.0 */ export const localeCompare = (that: string, locales?: Intl.LocalesArgument, options?: Intl.CollatorOptions) => (self: string): Ordering.Ordering => number.sign(self.localeCompare(that, locales, options)) /** * It is the `pipe`-able version of the native `match` method. * * @since 2.0.0 */ export const match = (regexp: RegExp | string) => (self: string): Option.Option<RegExpMatchArray> => Option.fromNullable(self.match(regexp)) /** * It is the `pipe`-able version of the native `matchAll` method. * * @since 2.0.0 */ export const matchAll = (regexp: RegExp) => (self: string): IterableIterator<RegExpMatchArray> => self.matchAll(regexp) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * const str = "\u1E9B\u0323"; * assert.deepStrictEqual(pipe(str, String.normalize()), "\u1E9B\u0323") * assert.deepStrictEqual(pipe(str, String.normalize("NFC")), "\u1E9B\u0323") * assert.deepStrictEqual(pipe(str, String.normalize("NFD")), "\u017F\u0323\u0307") * assert.deepStrictEqual(pipe(str, String.normalize("NFKC")), "\u1E69") * assert.deepStrictEqual(pipe(str, String.normalize("NFKD")), "\u0073\u0323\u0307") * ``` * * @since 2.0.0 */ export const normalize = (form?: "NFC" | "NFD" | "NFKC" | "NFKD") => (self: string): string => self.normalize(form) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * assert.deepStrictEqual(pipe("a", String.padEnd(5)), "a ") * assert.deepStrictEqual(pipe("a", String.padEnd(5, "_")), "a____") * ``` * * @since 2.0.0 */ export const padEnd = (maxLength: number, fillString?: string) => (self: string): string => self.padEnd(maxLength, fillString) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * assert.deepStrictEqual(pipe("a", String.padStart(5)), " a") * assert.deepStrictEqual(pipe("a", String.padStart(5, "_")), "____a") * ``` * * @since 2.0.0 */ export const padStart = (maxLength: number, fillString?: string) => (self: string): string => self.padStart(maxLength, fillString) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * assert.deepStrictEqual(pipe("a", String.repeat(5)), "aaaaa") * ``` * * @since 2.0.0 */ export const repeat = (count: number) => (self: string): string => self.repeat(count) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * assert.deepStrictEqual(pipe("ababb", String.replaceAll("b", "c")), "acacc") * assert.deepStrictEqual(pipe("ababb", String.replaceAll(/ba/g, "cc")), "accbb") * ``` * * @since 2.0.0 */ export const replaceAll = (searchValue: string | RegExp, replaceValue: string) => (self: string): string => self.replaceAll(searchValue, replaceValue) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("ababb", String.search("b")), Option.some(1)) * assert.deepStrictEqual(pipe("ababb", String.search(/abb/)), Option.some(2)) * assert.deepStrictEqual(pipe("ababb", String.search("d")), Option.none()) * ``` * * @since 2.0.0 */ export const search: { /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("ababb", String.search("b")), Option.some(1)) * assert.deepStrictEqual(pipe("ababb", String.search(/abb/)), Option.some(2)) * assert.deepStrictEqual(pipe("ababb", String.search("d")), Option.none()) * ``` * * @since 2.0.0 */ (regexp: RegExp | string): (self: string) => Option.Option<number> /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String, Option } from "effect" * * assert.deepStrictEqual(pipe("ababb", String.search("b")), Option.some(1)) * assert.deepStrictEqual(pipe("ababb", String.search(/abb/)), Option.some(2)) * assert.deepStrictEqual(pipe("ababb", String.search("d")), Option.none()) * ``` * * @since 2.0.0 */ (self: string, regexp: RegExp | string): Option.Option<number> } = dual( 2, (self: string, regexp: RegExp | string): Option.Option<number> => Option.filter(Option.some(self.search(regexp)), number.greaterThanOrEqualTo(0)) ) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * const str = "\u0130" * assert.deepStrictEqual(pipe(str, String.toLocaleLowerCase("tr")), "i") * ``` * * @since 2.0.0 */ export const toLocaleLowerCase = (locale?: Intl.LocalesArgument) => (self: string): string => self.toLocaleLowerCase(locale) /** * @example * ```ts * import * as assert from "node:assert" * import { pipe, String } from "effect" * * const str = "i\u0307" * assert.deepStrictEqual(pipe(str, String.toLocaleUpperCase("lt-LT")), "I") * ``` * * @since 2.0.0 */ export const toLocaleUpperCase = (locale?: Intl.LocalesArgument) => (self: string): string => self.toLocaleUpperCase(locale) /** * Keep the specified number of characters from the start of a string. * * If `n` is larger than the available number of characters, the string will * be returned whole. * * If `n` is not a positive number, an empty string will be returned. * * If `n` is a float, it will be rounded down to the nearest integer. * * @example * ```ts * import * as assert from "node:assert" * import { String } from "effect" * * assert.deepStrictEqual(String.takeLeft("Hello World", 5), "Hello") * ``` * * @since 2.0.0 */ export const takeLeft: { /** * Keep the specified number of characters from the start of a string. * * If `n` is larger than the available number of characters, the string will * be returned whole. * * If `n` is not a positive number, an empty string will be returned. * * If `n` is a float, it will be rounded down to the nearest integer. * * @example * ```ts * import * as assert from "node:assert" * import { String } from "effect" * * assert.deepStrictEqual(String.takeLeft("Hello World", 5), "Hello") * ``` * * @since 2.0.0 */ (n: number): (self: string) => string /** * Keep the specified number of characters from the start of a string. * * If `n` is larger than the available number of characters, the string will * be returned whole. * * If `n` is not a positive number, an empty string will be returned. * * If `n` is a float, it will be rounded down to the nearest integer. * * @example * ```ts * import * as assert from "node:assert" * import { String } from "effect" * * assert.deepStrictEqual(String.takeLeft("Hello World", 5), "Hello") * ``` * * @since 2.0.0 */ (self: string, n: number): string } = dual(2, (self: string, n: number): string => self.slice(0, Math.max(n, 0))) /** * Keep the specified number of characters from the end of a string. * * If `n` is larger than the available number of characters, the string will * be returned whole. * * If `n` is not a positive number, an empty string will be returned. * * If `n` is a float, it will be rounded down to the nearest integer. * * @example * ```ts * import * as assert from "node:assert" * import { String } from "effect" * * assert.deepStrictEqual(String.takeRight("Hello World", 5), "World") * ``` * * @since 2.0.0 */ export const takeRight: { /** * Keep the specified number of characters from the end of a string. * * If `n` is larger than the available number of characters, the string will * be returned whole. * * If `n` is not a positive number, an empty string will be returned. * * If `n` is a float, it will be rounded down to the nearest integer. * * @example * ```ts * import * as assert from "node:assert" * import { String } from "effect" * * assert.deepStrictEqual(String.takeRight("Hello World", 5), "World") * ``` * * @since 2.0.0 */ (n: number): (self: string) => string /** * Keep the specified number of characters from the end of a string. * * If `n` is larger than the available number of characters, the string will * be returned whole. * * If `n` is not a positive number, an empty string will be returned. * * If `n` is a float, it will be rounded down to the nearest integer. * * @example * ```ts * import * as assert from "node:assert" * import { String } from "effect" * * assert.deepStrictEqual(String.takeRight("Hello World", 5), "World") * ``` * * @since 2.0.0 */ (self: string, n: number): string } = dual( 2, (self: string, n: number): string => self.slice(Math.max(0, self.length - Math.floor(n)), Infinity) ) const CR = 0x0d const LF = 0x0a /** * Returns an `IterableIterator` which yields each line contained within the * string, trimming off the trailing newline character. * * @since 2.0.0 */ export const linesIterator = (self: string): LinesIterator => linesSeparated(self, true) /** * Returns an `IterableIterator` which yields each line contained within the * string as well as the trailing newline character. * * @since 2.0.0 */ export const linesWithSeparators = (s: string): LinesIterator => linesSeparated(s, false) /** * For every line in this string, strip a leading prefix consisting of blanks * or control characters followed by the character specified by `marginChar` * from the line. * * @since 2.0.0 */ export const stripMarginWith: { /** * For every line in this string, strip a leading prefix consisting of blanks * or control characters followed by the character specified by `marginChar` * from the line. * * @since 2.0.0 */ (marginChar: string): (self: string) => string /** * For every line in this string, strip a leading prefix consisting of blanks * or control characters followed by the character specified by `marginChar` * from the line. * * @since 2.0.0 */ (self: string, marginChar: string): string } = dual(2, (self: string, marginChar: string): string => { let out = "" for (const line of linesWithSeparators(self)) { let index = 0 while (index < line.length && line.charAt(index) <= " ") { index = index + 1 } const stripped = index < line.length && line.charAt(index) === marginChar ? line.substring(index + 1) : line out = out + stripped } return out }) /** * For every line in this string, strip a leading prefix consisting of blanks * or control characters followed by the `"|"` character from the line. * * @since 2.0.0 */ export const stripMargin = (self: string): string => stripMarginWith(self, "|") /** * @since 2.0.0 */ export const snakeToCamel = (self: string): string => { let str = self[0] for (let i = 1; i < self.length; i++) { str += self[i] === "_" ? self[++i].toUpperCase() : self[i] } return str } /** * @since 2.0.0 */ export const snakeToPascal = (self: string): string => { let str = self[0].toUpperCase() for (let i = 1; i < self.length; i++) { str += self[i] === "_" ? self[++i].toUpperCase() : self[i] } return str } /** * @since 2.0.0 */ export const snakeToKebab = (self: string): string => self.replace(/_/g, "-") /** * @since 2.0.0 */ export const camelToSnake = (self: string): string => self.replace(/([A-Z])/g, "_$1").toLowerCase() /** * @since 2.0.0 */ export const pascalToSnake = (self: string): string => (self.slice(0, 1) + self.slice(1).replace(/([A-Z])/g, "_$1")).toLowerCase() /** * @since 2.0.0 */ export const kebabToSnake = (self: string): string => self.replace(/-/g, "_") class LinesIterator implements IterableIterator<string> { private index: number private readonly length: number constructor(readonly s: string, readonly stripped: boolean = false) { this.index = 0 this.length = s.length } next(): IteratorResult<string> { if (this.done) { return { done: true, value: undefined } } const start = this.index while (!this.done && !isLineBreak(this.s[this.index]!)) { this.index = this.index + 1 } let end = this.index if (!this.done) { const char = this.s[this.index]! this.index = this.index + 1 if (!this.done && isLineBreak2(char, this.s[this.index]!)) { this.index = this.index + 1 } if (!this.stripped) { end = this.index } } return { done: false, value: this.s.substring(start, end) } } [Symbol.iterator](): IterableIterator<string> { return new LinesIterator(this.s, this.stripped) } private get done(): boolean { return this.index >= this.length } } /** * Test if the provided character is a line break character (i.e. either `"\r"` * or `"\n"`). */ const isLineBreak = (char: string): boolean => { const code = char.charCodeAt(0) return code === CR || code === LF } /** * Test if the provided characters combine to form a carriage return/line-feed * (i.e. `"\r\n"`). */ const isLineBreak2 = (char0: string, char1: string): boolean => char0.charCodeAt(0) === CR && char1.charCodeAt(0) === LF const linesSeparated = (self: string, stripped: boolean): LinesIterator => new LinesIterator(self, stripped)