// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at <https://mozilla.org/MPL/2.0/>.
+import { bind, call, identity, makeCallable } from "./function.js";
+import { getPrototype, objectCreate } from "./object.js";
+
+export const {
+ /**
+ * Returns the result of converting the provided value to A·S·C·I·I
+ * lowercase.
+ */
+ asciiLowercase,
+
+ /**
+ * Returns the result of converting the provided value to A·S·C·I·I
+ * uppercase.
+ */
+ asciiUppercase,
+} = (() => {
+ const {
+ toLowerCase: stringToLowercase,
+ toUpperCase: stringToUppercase,
+ } = String.prototype;
+ return {
+ asciiLowercase: ($) =>
+ stringReplaceAll(
+ `${$}`,
+ /[A-Z]/gu,
+ makeCallable(stringToLowercase),
+ ),
+ asciiUppercase: ($) =>
+ stringReplaceAll(
+ `${$}`,
+ /[a-z]/gu,
+ makeCallable(stringToUppercase),
+ ),
+ };
+})();
+
+export const {
+ /**
+ * Returns an iterator over the code units in the string
+ * representation of the provided value.
+ */
+ codeUnits,
+
+ /**
+ * Returns an iterator over the codepoints in the string
+ * representation of the provided value.
+ */
+ codepoints,
+
+ /**
+ * Returns an iterator over the scalar values in the string
+ * representation of the provided value.
+ *
+ * Codepoints which are not valid Unicode scalar values are replaced
+ * with U+FFFF.
+ */
+ scalarValues,
+
+ /**
+ * Returns the result of converting the provided value to a string of
+ * scalar values by replacing (unpaired) surrogate values with
+ * U+FFFD.
+ */
+ scalarValueString,
+} = (() => {
+ const {
+ iterator: iteratorSymbol,
+ toStringTag: toStringTagSymbol,
+ } = Symbol;
+ const { [iteratorSymbol]: arrayIterator } = Array.prototype;
+ const arrayIteratorPrototype = Object.getPrototypeOf(
+ [][iteratorSymbol](),
+ );
+ const { next: arrayIteratorNext } = arrayIteratorPrototype;
+ const iteratorPrototype = Object.getPrototypeOf(
+ arrayIteratorPrototype,
+ );
+ const { [iteratorSymbol]: stringIterator } = String.prototype;
+ const stringIteratorPrototype = Object.getPrototypeOf(
+ ""[iteratorSymbol](),
+ );
+ const { next: stringIteratorNext } = stringIteratorPrototype;
+
+ /**
+ * An iterator object for iterating over code values (either code
+ * units or codepoints) in a string.
+ *
+ * ※ This constructor is not exposed.
+ */
+ const StringCodeValueIterator = class extends identity {
+ #allowSurrogates;
+ #baseIterator;
+
+ /**
+ * Constructs a new string code value iterator from the provided
+ * base iterator.
+ *
+ * If the provided base iterator is an array iterator, this is a
+ * code unit iterator. If the provided iterator is a string
+ * iterator and surrogates are allowed, this is a codepoint
+ * iterator. If the provided iterator is a string iterator and
+ * surrogates are not allowed, this is a scalar value iterator.
+ */
+ constructor(baseIterator, allowSurrogates = true) {
+ super(objectCreate(stringCodeValueIteratorPrototype));
+ this.#allowSurrogates = !!allowSurrogates;
+ this.#baseIterator = baseIterator;
+ }
+
+ /** Provides the next code value in the iterator. */
+ next() {
+ const baseIterator = this.#baseIterator;
+ switch (getPrototype(baseIterator)) {
+ case arrayIteratorPrototype: {
+ // The base iterator is iterating over U·C·S characters.
+ const {
+ value: ucsCharacter,
+ done,
+ } = call(arrayIteratorNext, baseIterator, []);
+ return done
+ ? { value: undefined, done: true }
+ : { value: getCodeUnit(ucsCharacter, 0), done: false };
+ }
+ case stringIteratorPrototype: {
+ // The base iterator is iterating over Unicode characters.
+ const {
+ value: character,
+ done,
+ } = call(stringIteratorNext, baseIterator, []);
+ if (done) {
+ // The base iterator has been exhausted.
+ return { value: undefined, done: true };
+ } else {
+ // The base iterator provided a character; yield the
+ // codepoint.
+ const codepoint = getCodepoint(character, 0);
+ return {
+ value: this.#allowSurrogates || codepoint <= 0xD7FF ||
+ codepoint >= 0xE000
+ ? codepoint
+ : 0xFFFD,
+ done: false,
+ };
+ }
+ }
+ default: {
+ // Should not be possible!
+ throw new TypeError(
+ "Piscēs: Unrecognized base iterator type in %StringCodeValueIterator%.",
+ );
+ }
+ }
+ }
+ };
+
+ const {
+ next: stringCodeValueIteratorNext,
+ } = StringCodeValueIterator.prototype;
+ const stringCodeValueIteratorPrototype = objectCreate(
+ iteratorPrototype,
+ {
+ next: {
+ configurable: true,
+ enumerable: false,
+ value: stringCodeValueIteratorNext,
+ writable: true,
+ },
+ [toStringTagSymbol]: {
+ configurable: true,
+ enumerable: false,
+ value: "String Code Value Iterator",
+ writable: false,
+ },
+ },
+ );
+ const scalarValueIterablePrototype = {
+ [iteratorSymbol]() {
+ return {
+ next: bind(
+ stringCodeValueIteratorNext,
+ new StringCodeValueIterator(
+ call(stringIterator, this.source, []),
+ false,
+ ),
+ [],
+ ),
+ };
+ },
+ };
+
+ return {
+ codeUnits: ($) =>
+ new StringCodeValueIterator(call(arrayIterator, $, [])),
+ codepoints: ($) =>
+ new StringCodeValueIterator(
+ call(stringIterator, $, []),
+ true,
+ ),
+ scalarValues: ($) =>
+ new StringCodeValueIterator(
+ call(stringIterator, $, []),
+ false,
+ ),
+ scalarValueString: ($) =>
+ stringFromCodepoints(...objectCreate(
+ scalarValueIterablePrototype,
+ { source: { value: $ } },
+ )),
+ };
+})();
+
/**
- * Returns the result of converting the provided value to A·S·C·I·I
- * lowercase.
+ * Returns an iterator over the codepoints in the string representation
+ * of the provided value according to the algorithm of
+ * String::[Symbol.iterator].
*/
-export const asciiLowercase = ($) =>
- `${$}`.replaceAll(
- /[A-Z]/gu,
- Function.prototype.call.bind(String.prototype.toLowerCase),
- );
+export const characters = makeCallable(
+ String.prototype[Symbol.iterator],
+);
/**
- * Returns the result of converting the provided value to A·S·C·I·I
- * uppercase.
+ * Returns the character at the provided position in the string
+ * representation of the provided value according to the algorithm of
+ * String::codePointAt.
*/
-export const asciiUppercase = ($) =>
- `${$}`.replaceAll(
- /[a-z]/gu,
- Function.prototype.call.bind(String.prototype.toUpperCase),
- );
+export const getCharacter = ($, pos) => {
+ const codepoint = getCodepoint($, pos);
+ return codepoint == null
+ ? undefined
+ : stringFromCodepoints(codepoint);
+};
/**
- * Returns the result of converting the provided value to a string of
- * scalar values by replacing (unpaired) surrogate values with U+FFFD.
+ * Returns the code unit at the provided position in the string
+ * representation of the provided value according to the algorithm of
+ * String::charAt.
*/
-export const scalarValueString = ($) =>
- String.fromCodePoint(
- ...function* () {
- for (const char of `${$}`) {
- const scalar = char.codePointAt(0);
- yield scalar >= 0xD800 && scalar <= 0xDFFF ? 0xFFFD : scalar;
- }
- }(),
- );
+export const getCodeUnit = makeCallable(String.prototype.charCodeAt);
+
+/**
+ * Returns the codepoint at the provided position in the string
+ * representation of the provided value according to the algorithm of
+ * String::codePointAt.
+ */
+export const getCodepoint = makeCallable(String.prototype.codePointAt);
+
+/**
+ * Returns the index of the first occurrence of the search string in
+ * the string representation of the provided value according to the
+ * algorithm of String::indexOf.
+ */
+export const getFirstSubstringIndex = makeCallable(
+ String.prototype.indexOf,
+);
+
+/**
+ * Returns the index of the last occurrence of the search string in the
+ * string representation of the provided value according to the
+ * algorithm of String::lastIndexOf.
+ */
+export const getLastSubstringIndex = makeCallable(
+ String.prototype.lastIndexOf,
+);
+
+/**
+ * Returns the result of joining the provided iterable.
+ *
+ * If no separator is provided, it defaults to ",".
+ *
+ * If a value is nullish, it will be stringified as the empty string.
+ */
+export const join = (() => {
+ const { join: arrayJoin } = Array.prototype;
+ const join = ($, separator = ",") =>
+ call(arrayJoin, [...$], [`${separator}`]);
+ return join;
+})();
+
+export const {
+ /**
+ * Returns a string created from the raw value of the tagged template
+ * literal.
+ *
+ * ※ This is an alias for String.raw.
+ */
+ raw: rawString,
+
+ /**
+ * Returns a string created from the provided code units.
+ *
+ * ※ This is an alias for String.fromCharCode.
+ */
+ fromCharCode: stringFromCodeUnits,
+
+ /**
+ * Returns a string created from the provided codepoints.
+ *
+ * ※ This is an alias for String.fromCodePoint.
+ */
+ fromCodePoint: stringFromCodepoints,
+} = String;
/**
* Returns the result of splitting the provided value on A·S·C·I·I
* whitespace.
*/
export const splitOnASCIIWhitespace = ($) =>
- stripAndCollapseASCIIWhitespace($).split(" ");
+ stringSplit(stripAndCollapseASCIIWhitespace($), " ");
/**
* Returns the result of splitting the provided value on commas,
* trimming A·S·C·I·I whitespace from the resulting tokens.
*/
export const splitOnCommas = ($) =>
- stripLeadingAndTrailingASCIIWhitespace(
- `${$}`.replaceAll(
- /[\n\r\t\f ]*,[\n\r\t\f ]*/gu,
- ",",
+ stringSplit(
+ stripLeadingAndTrailingASCIIWhitespace(
+ stringReplaceAll(
+ `${$}`,
+ /[\n\r\t\f ]*,[\n\r\t\f ]*/gu,
+ ",",
+ ),
),
- ).split(",");
+ ",",
+ );
/**
- * Returns the result of stripping leading and trailing A·S·C·I·I
- * whitespace from the provided value.
+ * Returns the result of catenating the string representations of the
+ * provided values, returning a new string according to the algorithm
+ * of String::concat.
*/
-export const stripLeadingAndTrailingASCIIWhitespace = ($) =>
- /^[\n\r\t\f ]*([^]*?)[\n\r\t\f ]*$/u.exec($)[1];
+export const stringCatenate = makeCallable(String.prototype.concat);
+
+/**
+ * Returns whether the string representation of the provided value ends
+ * with the provided search string according to the algorithm of
+ * String::endsWith.
+ */
+export const stringEndsWith = makeCallable(String.prototype.endsWith);
+
+/**
+ * Returns whether the string representation of the provided value
+ * contains the provided search string according to the algorithm of
+ * String::includes.
+ */
+export const stringIncludes = makeCallable(String.prototype.includes);
+
+/**
+ * Returns the result of matching the string representation of the
+ * provided value with the provided matcher according to the algorithm
+ * of String::match.
+ */
+export const stringMatch = makeCallable(String.prototype.match);
+
+/**
+ * Returns the result of matching the string representation of the
+ * provided value with the provided matcher according to the algorithm
+ * of String::matchAll.
+ */
+export const stringMatchAll = makeCallable(String.prototype.matchAll);
+
+/**
+ * Returns the normalized form of the string representation of the
+ * provided value according to the algorithm of String::matchAll.
+ */
+export const stringNormalize = makeCallable(
+ String.prototype.normalize,
+);
+
+/**
+ * Returns the result of padding the end of the string representation
+ * of the provided value padded until it is the desired length
+ * according to the algorithm of String::padEnd.
+ */
+export const stringPadEnd = makeCallable(String.prototype.padEnd);
+
+/**
+ * Returns the result of padding the start of the string representation
+ * of the provided value padded until it is the desired length
+ * according to the algorithm of String::padStart.
+ */
+export const stringPadStart = makeCallable(String.prototype.padStart);
+
+/**
+ * Returns the result of repeating the string representation of the
+ * provided value the provided number of times according to the
+ * algorithm of String::repeat.
+ */
+export const stringRepeat = makeCallable(String.prototype.repeat);
+
+/**
+ * Returns the result of replacing the string representation of the
+ * provided value with the provided replacement, using the provided
+ * matcher and according to the algorithm of String::replace.
+ */
+export const stringReplace = makeCallable(String.prototype.replace);
+
+/**
+ * Returns the result of replacing the string representation of the
+ * provided value with the provided replacement, using the provided
+ * matcher and according to the algorithm of String::replaceAll.
+ */
+export const stringReplaceAll = makeCallable(
+ String.prototype.replaceAll,
+);
+
+/**
+ * Returns the result of searching the string representation of the
+ * provided value using the provided matcher and according to the
+ * algorithm of String::search.
+ */
+export const stringSearch = makeCallable(String.prototype.search);
+
+/**
+ * Returns a slice of the string representation of the provided value
+ * according to the algorithm of String::slice.
+ */
+export const stringSlice = makeCallable(String.prototype.slice);
+
+/**
+ * Returns the result of splitting of the string representation of the
+ * provided value on the provided separator according to the algorithm
+ * of String::split.
+ */
+export const stringSplit = makeCallable(String.prototype.split);
+
+/**
+ * Returns whether the string representation of the provided value
+ * starts with the provided search string according to the algorithm of
+ * String::startsWith.
+ */
+export const stringStartsWith = makeCallable(
+ String.prototype.startsWith,
+);
+
+/**
+ * Returns the `[[StringData]]` of the provided value.
+ *
+ * ☡ This function will throw if the provided object does not have a
+ * `[[StringData]]` internal slot.
+ */
+export const stringValue = makeCallable(String.prototype.valueOf);
/**
* Returns the result of stripping leading and trailing A·S·C·I·I
* whitespace from the provided value and collapsing other A·S·C·I·I
- * whitespace in the provided value.
+ * whitespace in the string representation of the provided value.
*/
export const stripAndCollapseASCIIWhitespace = ($) =>
stripLeadingAndTrailingASCIIWhitespace(
- `${$}`.replaceAll(
+ stringReplaceAll(
+ `${$}`,
/[\n\r\t\f ]+/gu,
" ",
),
);
+
+/**
+ * Returns the result of stripping leading and trailing A·S·C·I·I
+ * whitespace from the string representation of the provided value.
+ */
+export const stripLeadingAndTrailingASCIIWhitespace = (() => {
+ const { exec: reExec } = RegExp.prototype;
+ return ($) =>
+ call(reExec, /^[\n\r\t\f ]*([^]*?)[\n\r\t\f ]*$/u, [$])[1];
+})();
+
+/**
+ * Returns a substring of the string representation of the provided
+ * value according to the algorithm of String::substring.
+ */
+export const substring = makeCallable(String.prototype.substring);
Lady’s Gitweb / Pisces / blobdiff