Most of this was taken from الرشآء.
--- /dev/null
+Mozilla Public License Version 2.0
+==================================
+
+1. Definitions
+--------------
+
+1.1. "Contributor"
+ means each individual or legal entity that creates, contributes to
+ the creation of, or owns Covered Software.
+
+1.2. "Contributor Version"
+ means the combination of the Contributions of others (if any) used
+ by a Contributor and that particular Contributor's Contribution.
+
+1.3. "Contribution"
+ means Covered Software of a particular Contributor.
+
+1.4. "Covered Software"
+ means Source Code Form to which the initial Contributor has attached
+ the notice in Exhibit A, the Executable Form of such Source Code
+ Form, and Modifications of such Source Code Form, in each case
+ including portions thereof.
+
+1.5. "Incompatible With Secondary Licenses"
+ means
+
+ (a) that the initial Contributor has attached the notice described
+ in Exhibit B to the Covered Software; or
+
+ (b) that the Covered Software was made available under the terms of
+ version 1.1 or earlier of the License, but not also under the
+ terms of a Secondary License.
+
+1.6. "Executable Form"
+ means any form of the work other than Source Code Form.
+
+1.7. "Larger Work"
+ means a work that combines Covered Software with other material, in
+ a separate file or files, that is not Covered Software.
+
+1.8. "License"
+ means this document.
+
+1.9. "Licensable"
+ means having the right to grant, to the maximum extent possible,
+ whether at the time of the initial grant or subsequently, any and
+ all of the rights conveyed by this License.
+
+1.10. "Modifications"
+ means any of the following:
+
+ (a) any file in Source Code Form that results from an addition to,
+ deletion from, or modification of the contents of Covered
+ Software; or
+
+ (b) any new file in Source Code Form that contains any Covered
+ Software.
+
+1.11. "Patent Claims" of a Contributor
+ means any patent claim(s), including without limitation, method,
+ process, and apparatus claims, in any patent Licensable by such
+ Contributor that would be infringed, but for the grant of the
+ License, by the making, using, selling, offering for sale, having
+ made, import, or transfer of either its Contributions or its
+ Contributor Version.
+
+1.12. "Secondary License"
+ means either the GNU General Public License, Version 2.0, the GNU
+ Lesser General Public License, Version 2.1, the GNU Affero General
+ Public License, Version 3.0, or any later versions of those
+ licenses.
+
+1.13. "Source Code Form"
+ means the form of the work preferred for making modifications.
+
+1.14. "You" (or "Your")
+ means an individual or a legal entity exercising rights under this
+ License. For legal entities, "You" includes any entity that
+ controls, is controlled by, or is under common control with You. For
+ purposes of this definition, "control" means (a) the power, direct
+ or indirect, to cause the direction or management of such entity,
+ whether by contract or otherwise, or (b) ownership of more than
+ fifty percent (50%) of the outstanding shares or beneficial
+ ownership of such entity.
+
+2. License Grants and Conditions
+--------------------------------
+
+2.1. Grants
+
+Each Contributor hereby grants You a world-wide, royalty-free,
+non-exclusive license:
+
+(a) under intellectual property rights (other than patent or trademark)
+ Licensable by such Contributor to use, reproduce, make available,
+ modify, display, perform, distribute, and otherwise exploit its
+ Contributions, either on an unmodified basis, with Modifications, or
+ as part of a Larger Work; and
+
+(b) under Patent Claims of such Contributor to make, use, sell, offer
+ for sale, have made, import, and otherwise transfer either its
+ Contributions or its Contributor Version.
+
+2.2. Effective Date
+
+The licenses granted in Section 2.1 with respect to any Contribution
+become effective for each Contribution on the date the Contributor first
+distributes such Contribution.
+
+2.3. Limitations on Grant Scope
+
+The licenses granted in this Section 2 are the only rights granted under
+this License. No additional rights or licenses will be implied from the
+distribution or licensing of Covered Software under this License.
+Notwithstanding Section 2.1(b) above, no patent license is granted by a
+Contributor:
+
+(a) for any code that a Contributor has removed from Covered Software;
+ or
+
+(b) for infringements caused by: (i) Your and any other third party's
+ modifications of Covered Software, or (ii) the combination of its
+ Contributions with other software (except as part of its Contributor
+ Version); or
+
+(c) under Patent Claims infringed by Covered Software in the absence of
+ its Contributions.
+
+This License does not grant any rights in the trademarks, service marks,
+or logos of any Contributor (except as may be necessary to comply with
+the notice requirements in Section 3.4).
+
+2.4. Subsequent Licenses
+
+No Contributor makes additional grants as a result of Your choice to
+distribute the Covered Software under a subsequent version of this
+License (see Section 10.2) or under the terms of a Secondary License (if
+permitted under the terms of Section 3.3).
+
+2.5. Representation
+
+Each Contributor represents that the Contributor believes its
+Contributions are its original creation(s) or it has sufficient rights
+to grant the rights to its Contributions conveyed by this License.
+
+2.6. Fair Use
+
+This License is not intended to limit any rights You have under
+applicable copyright doctrines of fair use, fair dealing, or other
+equivalents.
+
+2.7. Conditions
+
+Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted
+in Section 2.1.
+
+3. Responsibilities
+-------------------
+
+3.1. Distribution of Source Form
+
+All distribution of Covered Software in Source Code Form, including any
+Modifications that You create or to which You contribute, must be under
+the terms of this License. You must inform recipients that the Source
+Code Form of the Covered Software is governed by the terms of this
+License, and how they can obtain a copy of this License. You may not
+attempt to alter or restrict the recipients' rights in the Source Code
+Form.
+
+3.2. Distribution of Executable Form
+
+If You distribute Covered Software in Executable Form then:
+
+(a) such Covered Software must also be made available in Source Code
+ Form, as described in Section 3.1, and You must inform recipients of
+ the Executable Form how they can obtain a copy of such Source Code
+ Form by reasonable means in a timely manner, at a charge no more
+ than the cost of distribution to the recipient; and
+
+(b) You may distribute such Executable Form under the terms of this
+ License, or sublicense it under different terms, provided that the
+ license for the Executable Form does not attempt to limit or alter
+ the recipients' rights in the Source Code Form under this License.
+
+3.3. Distribution of a Larger Work
+
+You may create and distribute a Larger Work under terms of Your choice,
+provided that You also comply with the requirements of this License for
+the Covered Software. If the Larger Work is a combination of Covered
+Software with a work governed by one or more Secondary Licenses, and the
+Covered Software is not Incompatible With Secondary Licenses, this
+License permits You to additionally distribute such Covered Software
+under the terms of such Secondary License(s), so that the recipient of
+the Larger Work may, at their option, further distribute the Covered
+Software under the terms of either this License or such Secondary
+License(s).
+
+3.4. Notices
+
+You may not remove or alter the substance of any license notices
+(including copyright notices, patent notices, disclaimers of warranty,
+or limitations of liability) contained within the Source Code Form of
+the Covered Software, except that You may alter any license notices to
+the extent required to remedy known factual inaccuracies.
+
+3.5. Application of Additional Terms
+
+You may choose to offer, and to charge a fee for, warranty, support,
+indemnity or liability obligations to one or more recipients of Covered
+Software. However, You may do so only on Your own behalf, and not on
+behalf of any Contributor. You must make it absolutely clear that any
+such warranty, support, indemnity, or liability obligation is offered by
+You alone, and You hereby agree to indemnify every Contributor for any
+liability incurred by such Contributor as a result of warranty, support,
+indemnity or liability terms You offer. You may include additional
+disclaimers of warranty and limitations of liability specific to any
+jurisdiction.
+
+4. Inability to Comply Due to Statute or Regulation
+---------------------------------------------------
+
+If it is impossible for You to comply with any of the terms of this
+License with respect to some or all of the Covered Software due to
+statute, judicial order, or regulation then You must: (a) comply with
+the terms of this License to the maximum extent possible; and (b)
+describe the limitations and the code they affect. Such description must
+be placed in a text file included with all distributions of the Covered
+Software under this License. Except to the extent prohibited by statute
+or regulation, such description must be sufficiently detailed for a
+recipient of ordinary skill to be able to understand it.
+
+5. Termination
+--------------
+
+5.1. The rights granted under this License will terminate automatically
+if You fail to comply with any of its terms. However, if You become
+compliant, then the rights granted under this License from a particular
+Contributor are reinstated (a) provisionally, unless and until such
+Contributor explicitly and finally terminates Your grants, and (b) on an
+ongoing basis, if such Contributor fails to notify You of the
+non-compliance by some reasonable means prior to 60 days after You have
+come back into compliance. Moreover, Your grants from a particular
+Contributor are reinstated on an ongoing basis if such Contributor
+notifies You of the non-compliance by some reasonable means, this is the
+first time You have received notice of non-compliance with this License
+from such Contributor, and You become compliant prior to 30 days after
+Your receipt of the notice.
+
+5.2. If You initiate litigation against any entity by asserting a patent
+infringement claim (excluding declaratory judgment actions,
+counter-claims, and cross-claims) alleging that a Contributor Version
+directly or indirectly infringes any patent, then the rights granted to
+You by any and all Contributors for the Covered Software under Section
+2.1 of this License shall terminate.
+
+5.3. In the event of termination under Sections 5.1 or 5.2 above, all
+end user license agreements (excluding distributors and resellers) which
+have been validly granted by You or Your distributors under this License
+prior to termination shall survive termination.
+
+************************************************************************
+* *
+* 6. Disclaimer of Warranty *
+* ------------------------- *
+* *
+* Covered Software is provided under this License on an "as is" *
+* basis, without warranty of any kind, either expressed, implied, or *
+* statutory, including, without limitation, warranties that the *
+* Covered Software is free of defects, merchantable, fit for a *
+* particular purpose or non-infringing. The entire risk as to the *
+* quality and performance of the Covered Software is with You. *
+* Should any Covered Software prove defective in any respect, You *
+* (not any Contributor) assume the cost of any necessary servicing, *
+* repair, or correction. This disclaimer of warranty constitutes an *
+* essential part of this License. No use of any Covered Software is *
+* authorized under this License except under this disclaimer. *
+* *
+************************************************************************
+
+************************************************************************
+* *
+* 7. Limitation of Liability *
+* -------------------------- *
+* *
+* Under no circumstances and under no legal theory, whether tort *
+* (including negligence), contract, or otherwise, shall any *
+* Contributor, or anyone who distributes Covered Software as *
+* permitted above, be liable to You for any direct, indirect, *
+* special, incidental, or consequential damages of any character *
+* including, without limitation, damages for lost profits, loss of *
+* goodwill, work stoppage, computer failure or malfunction, or any *
+* and all other commercial damages or losses, even if such party *
+* shall have been informed of the possibility of such damages. This *
+* limitation of liability shall not apply to liability for death or *
+* personal injury resulting from such party's negligence to the *
+* extent applicable law prohibits such limitation. Some *
+* jurisdictions do not allow the exclusion or limitation of *
+* incidental or consequential damages, so this exclusion and *
+* limitation may not apply to You. *
+* *
+************************************************************************
+
+8. Litigation
+-------------
+
+Any litigation relating to this License may be brought only in the
+courts of a jurisdiction where the defendant maintains its principal
+place of business and such litigation shall be governed by laws of that
+jurisdiction, without reference to its conflict-of-law provisions.
+Nothing in this Section shall prevent a party's ability to bring
+cross-claims or counter-claims.
+
+9. Miscellaneous
+----------------
+
+This License represents the complete agreement concerning the subject
+matter hereof. If any provision of this License is held to be
+unenforceable, such provision shall be reformed only to the extent
+necessary to make it enforceable. Any law or regulation which provides
+that the language of a contract shall be construed against the drafter
+shall not be used to construe this License against a Contributor.
+
+10. Versions of the License
+---------------------------
+
+10.1. New Versions
+
+Mozilla Foundation is the license steward. Except as provided in Section
+10.3, no one other than the license steward has the right to modify or
+publish new versions of this License. Each version will be given a
+distinguishing version number.
+
+10.2. Effect of New Versions
+
+You may distribute the Covered Software under the terms of the version
+of the License under which You originally received the Covered Software,
+or under the terms of any subsequent version published by the license
+steward.
+
+10.3. Modified Versions
+
+If you create software not governed by this License, and you want to
+create a new license for such software, you may create and use a
+modified version of this License if you rename the license and remove
+any references to the name of the license steward (except to note that
+such modified license differs from this License).
+
+10.4. Distributing Source Code Form that is Incompatible With Secondary
+Licenses
+
+If You choose to distribute Source Code Form that is Incompatible With
+Secondary Licenses under the terms of this version of the License, the
+notice described in Exhibit B of this License must be attached.
+
+Exhibit A - Source Code Form License Notice
+-------------------------------------------
+
+ This Source Code Form is subject to the terms of the Mozilla Public
+ 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/.
+
+If it is not possible or desirable to put the notice in a particular
+file, then You may include the notice in a location (such as a LICENSE
+file in a relevant directory) where a recipient would be likely to look
+for such a notice.
+
+You may add additional accurate notices of copyright ownership.
+
+Exhibit B - "Incompatible With Secondary Licenses" Notice
+---------------------------------------------------------
+
+ This Source Code Form is "Incompatible With Secondary Licenses", as
+ defined by the Mozilla Public License, v. 2.0.
--- /dev/null
+# ♓🧩 Piscēs
+
+<b>Ecmascript building blocks.</b>
+
+<dfn>♓🧩 Piscēs</dfn> is a Javascript (handcoded Ecmascript) library
+providing various building blocks for developing complex,
+precisely‐defined Javascript libraries. It provides implementations of
+fundamental Ecmascript Specification functions for use in Javascript
+code, plus other helpful prototypes and utilities.
+
+This library is **targeted at “low‐level” Javascript development**, i·e
+the kind of development undertaken with the Ecmascript specification
+open as reference. Taking full advantage of it requires familiarity
+with things like `Reflect` and a willingness to access properties and
+methods from one prototype on an unrelated object.
+
+**♓🧩 Piscēs was written to serve the interests of
+[♓🌟 الرشآء](https://git.ladys.computer/Alrescha) development, and not
+as a general‐use library.** This means that it is not extensively
+documented beyond its source code, it is not rigidly versioned, and it
+offers no guarantees regarding stability between versions. However, it
+is written in a generic manner, such that if you find it useful, you
+_can_ integrate it into your project—using ordinary Ecmascript imports
+from `https://git.ladys.computer/Pisces/blob_plain/❲HASH❳:/mod.js`.
+Always use a specific hash, and not a branch name like `current`, when
+importing ♓🧩 Piscēs into your project.
+
+Piscēs is broken up into multiple files, which is perfectly acceptable
+for use with [Deno](https://deno.land), but generally not considered
+ideal for usage on the web. You can use the `deno bundle` command to
+stitch the various source files together into a single script.
+
+## License
+
+Source files are licensed under the terms of the <cite>Mozilla Public
+License, version 2.0</cite>. For more information, see
+[LICENSE](./LICENSE).
--- /dev/null
+// ♓🌟 Piscēs ∷ base64.js
+// ====================================================================
+//
+// Copyright © 2020–2022 Lady [@ Lady’s Computer].
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// 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/>.
+
+/**
+ * Returns an ArrayBuffer generated from the provided Base64.
+ *
+ * This function can also be used as a tag for a template literal. The
+ * literal will be interpreted akin to `String.raw`.
+ */
+export const a2b = ($, ...$s) => {
+ const source = (
+ typeof $ == "string"
+ ? $
+ : Object.hasOwn($, "raw")
+ ? String.raw($, ...$s)
+ : `${$}`
+ ).replace(/[\t\n\f\r ]+/gu, "");
+ const u6s = Array.prototype.map.call(
+ source.length % 4 == 0 ? source.replace(/={1,2}$/u, "") : source,
+ (character) => {
+ const code = character.charCodeAt(0);
+ const result = code >= 0x41 && code <= 0x5A
+ ? code - 65
+ : code >= 0x61 && code <= 0x7A
+ ? code - 71
+ : code >= 0x30 && code <= 0x39
+ ? code + 4
+ : code == 0x2B
+ ? 62
+ : code == 0x2F
+ ? 63
+ : -1;
+ if (result < 0) {
+ throw new RangeError(
+ `Piscēs: Invalid character in Base64: ${character}.`,
+ );
+ } else {
+ return result;
+ }
+ },
+ );
+ const { length } = u6s;
+ const dataView = new DataView(
+ new ArrayBuffer(Math.floor(length * 3 / 4)),
+ );
+ for (let index = 0; index < length - 1;) {
+ const dataIndex = Math.ceil(index * 3 / 4);
+ const remainder = index % 3;
+ if (remainder == 0) {
+ dataView.setUint8(
+ dataIndex,
+ (u6s[index] << 2) + (u6s[++index] >> 4),
+ );
+ } else if (remainder == 1) {
+ dataView.setUint8(
+ dataIndex,
+ ((u6s[index] & 0xF) << 4) + (u6s[++index] >> 2),
+ );
+ } else {
+ dataView.setUint8(
+ dataIndex,
+ ((u6s[index] & 0x3) << 6) + u6s[++index],
+ );
+ }
+ }
+ return dataView.buffer;
+};
+
+/**
+ * Returns a (big‐endian) base64 string created from a typed array,
+ * buffer, or string.
+ *
+ * This function can also be used as a tag for a template literal. The
+ * literal will be interpreted akin to `String.raw`.
+ */
+export const b2a = ($, ...$s) => {
+ const buffer = $ instanceof ArrayBuffer
+ ? $
+ : $ instanceof DataView ||
+ $ instanceof Object.getPrototypeOf(Uint8Array)
+ ? $.buffer
+ : ((string) =>
+ Array.prototype.reduce.call(
+ string,
+ (result, code·point, index) => (
+ result.setUint16(index * 2, code·point.charCodeAt(0)), result
+ ),
+ new DataView(new ArrayBuffer(string.length * 2)),
+ ).buffer)(
+ typeof $ == "string"
+ ? $
+ : Object.hasOwn($, "raw")
+ ? String.raw($, ...$s)
+ : `${$}`,
+ );
+ const dataView = new DataView(buffer);
+ const { byteLength } = buffer;
+ const minimumLengthOfResults = Math.ceil(byteLength * 4 / 3);
+ const resultingCode·points = new Array(
+ minimumLengthOfResults + (4 - (minimumLengthOfResults % 4)) % 4,
+ ).fill(0x3D);
+ for (let index = 0; index < byteLength;) {
+ const code·pointIndex = Math.ceil(index * 4 / 3);
+ const currentIndex = code·pointIndex + +(
+ index % 3 == 0 && resultingCode·points[code·pointIndex] != 0x3D
+ );
+ const remainder = currentIndex % 4;
+ const u6 = remainder == 0
+ ? dataView.getUint8(index) >> 2
+ : remainder == 1
+ ? ((dataView.getUint8(index++) & 0x3) << 4) +
+ (index < byteLength ? dataView.getUint8(index) >> 4 : 0)
+ : remainder == 2
+ ? ((dataView.getUint8(index++) & 0xF) << 2) +
+ (index < byteLength ? dataView.getUint8(index) >> 6 : 0)
+ : dataView.getUint8(index++) & 0x3F;
+ const result = u6 < 26
+ ? u6 + 65
+ : u6 < 52
+ ? u6 + 71
+ : u6 < 62
+ ? u6 - 4
+ : u6 < 63
+ ? 43
+ : u6 < 64
+ ? 47
+ : -1;
+ if (result < 0) {
+ throw new RangeError(`Piscēs: Unexpected Base64 value: ${u6}.`);
+ } else {
+ resultingCode·points[currentIndex] = result;
+ }
+ }
+ return String.fromCodePoint(...resultingCode·points);
+};
+
+/**
+ * Returns whether the provided value is a Base64 string.
+ *
+ * Returns false if the provided value is not a string primitive.
+ */
+export const isBase64 = ($) => {
+ if (typeof $ != "string") return false;
+ const source = $.replace(/[\t\n\f\r ]+/gu, "");
+ const trimmed = source.length % 4 == 0
+ ? source.replace(/={1,2}$/u, "")
+ : source;
+ return trimmed.length % 4 != 1 &&
+ !/[^0-9A-Za-z+\/]/u.test(trimmed);
+};
--- /dev/null
+// ♓🌟 Piscēs ∷ base64.test.js
+// ====================================================================
+//
+// Copyright © 2020–2022 Lady [@ Lady’s Computer].
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// 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 { a2b, b2a, isBase64 } from "./base64.js";
+import {
+ assert,
+ assertEquals,
+ assertStrictEquals,
+ assertThrows,
+} from "./dev-deps.js";
+
+const base64s = {
+ "AGIAYQBzAGUANgA0": "base64",
+ "R/Q=": new Uint16Array([62535]),
+ "S0lCSQ==": new Uint8ClampedArray([75, 73, 66, 73]).buffer,
+ YmFzZTY0: new DataView(
+ new Uint8Array([98, 97, 115, 101, 54, 52]).buffer,
+ ),
+};
+
+Deno.test({
+ name: "Calling b2a returns the correct string.",
+ fn: () =>
+ Object.entries(base64s).forEach(([key, value]) =>
+ assertStrictEquals(b2a(value), key)
+ ),
+});
+
+Deno.test({
+ name: "Calling a2b returns the correct data.",
+ fn: () => {
+ assertEquals(
+ a2b("AGIAYQBzAGUANgA0"),
+ new Uint8Array(
+ Array.prototype.map.call(
+ "\u{0}b\u{0}a\u{0}s\u{0}e\u{0}6\u{0}4",
+ ($) => $.charCodeAt(0),
+ ),
+ ).buffer,
+ );
+ assertEquals(
+ a2b("R/Q="),
+ new Uint16Array([62535]).buffer,
+ );
+ assertEquals(
+ a2b("S0lCSQ=="),
+ new Uint8ClampedArray([75, 73, 66, 73]).buffer,
+ );
+ assertEquals(
+ a2b("YmFzZTY0"),
+ new Uint8Array([98, 97, 115, 101, 54, 52]).buffer,
+ );
+ },
+});
+
+Deno.test({
+ name: "Calling a2b throws when provided with an invalid character.",
+ fn: () => assertThrows(() => a2b("abc_")),
+});
+
+Deno.test({
+ name: "Calling a2b throws when provided with an invalid equals.",
+ fn: () => assertThrows(() => a2b("abc==")),
+});
+
+Deno.test({
+ name:
+ "Calling a2b throws when provided with a length with a remainder of 1 when divided by 4.",
+ fn: () => {
+ assertThrows(() => a2b("abcde"));
+ assertThrows(() => a2b("abcde==="));
+ },
+});
+
+Deno.test({
+ name: "isBase64 returns true for base64 strings.",
+ fn: () =>
+ Object.keys(base64s).forEach((key) => assert(isBase64(key))),
+});
+
+Deno.test({
+ name: "isBase64 returns false for others.",
+ fn: () =>
+ [
+ undefined,
+ null,
+ true,
+ Symbol(),
+ 27,
+ 98n,
+ {},
+ [],
+ () => {},
+ new Proxy({}, {}),
+ "abc_",
+ "a",
+ "abc==",
+ ].forEach((value) => assert(!isBase64(value))),
+});
--- /dev/null
+// ♓🌟 Piscēs ∷ collection.js
+// ====================================================================
+//
+// Copyright © 2020–2022 Lady [@ Lady’s Computer].
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// 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 { MAX_SAFE_INTEGER } from "./numeric.js";
+import { isObject } from "./object.js";
+
+/**
+ * Returns -0 if the provided argument is "-0"; returns a number
+ * representing the index if the provided argument is a canonical
+ * numeric index string; otherwise, returns undefined.
+ *
+ * There is no clamping of the numeric index, but note that numbers
+ * above 2^53 − 1 are not safe nor valid integer indices.
+ */
+export const canonicalNumericIndexString = ($) => {
+ if (typeof $ != "string") {
+ return undefined;
+ } else if ($ === "-0") {
+ return -0;
+ } else {
+ const n = +$;
+ return $ === `${n}` ? n : undefined;
+ }
+};
+
+/** Returns whether the provided value is an array index. */
+export const isArrayIndex = ($) => {
+ const value = canonicalNumericIndexString($);
+ if (value !== undefined) {
+ return Object.is(value, 0) || value > 0 && value < -1 >>> 0;
+ } else {
+ return false;
+ }
+};
+
+/**
+ * Returns whether the provided object is a collection.
+ *
+ * The definition of “collection” used by Piscēs is similar to
+ * Ecmascript’s definition of an arraylike object, but it differs in
+ * a few ways :—
+ *
+ * - It requires the provided value to be a proper object.
+ *
+ * - It requires the `length` property to be an integer corresponding
+ * to an integer index.
+ *
+ * - It requires the object to be concat‐spreadable, meaning it must
+ * either be an array or have `[Symbol.isConcatSpreadable]` be true.
+ */
+export const isCollection = ($) => {
+ if (!(isObject($) && "length" in $)) {
+ // The provided value is not an object or does not have a `length`.
+ return false;
+ } else {
+ try {
+ toIndex($.length); // will throw if `length` is not an index
+ return isConcatSpreadable($);
+ } catch {
+ return false;
+ }
+ }
+};
+
+/**
+ * Returns whether the provided value is spreadable during array
+ * concatenation.
+ *
+ * This is also used to determine which things should be treated as
+ * collections.
+ */
+export const isConcatSpreadable = ($) => {
+ if (!isObject($)) {
+ // The provided value is not an object.
+ return false;
+ } else {
+ // The provided value is an object.
+ return !!($[Symbol.isConcatSpreadable] ?? Array.isArray($));
+ }
+};
+
+/** Returns whether the provided value is an integer index. */
+export const isIntegerIndex = ($) => {
+ const value = canonicalNumericIndexString($);
+ if (value !== undefined) {
+ return Object.is(value, 0) ||
+ value > 0 && value <= MAX_SAFE_INTEGER;
+ } else {
+ return false;
+ }
+};
+
+/**
+ * Returns the length of the provided arraylike object.
+ *
+ * Will throw if the provided object is not arraylike.
+ *
+ * This produces larger lengths than can actually be stored in arrays,
+ * because no such restrictions exist on arraylike methods. Use
+ * `isIndex` to determine if a value is an actual array index.
+ */
+export const lengthOfArrayLike = ({ length }) => {
+ return toLength(length);
+};
+
+/**
+ * Converts the provided value to an array index, or throws an error if
+ * it is out of range.
+ */
+export const toIndex = ($) => {
+ const integer = Math.floor($);
+ if (isNaN(integer) || integer == 0) {
+ // The value is zero·like.
+ return 0;
+ } else {
+ // The value is not zero·like.
+ const clamped = toLength(integer);
+ if (clamped !== integer) {
+ // Clamping the value changes it.
+ throw new RangeError(`Piscēs: Index out of range: ${$}.`);
+ } else {
+ // The value is within appropriate bounds.
+ return integer;
+ }
+ }
+};
+
+/** Converts the provided value to a length. */
+export const toLength = ($) => {
+ const len = Math.floor($);
+ return isNaN(len) || len == 0
+ ? 0
+ : Math.max(Math.min(len, MAX_SAFE_INTEGER), 0);
+};
--- /dev/null
+{
+ "fmt": { "options": { "lineWidth": 71 } },
+ "lint": { "rules": { "exclude": ["no-irregular-whitespace"] } }
+}
--- /dev/null
+// ♓🌟 Piscēs ∷ dev-deps.js
+// ====================================================================
+//
+// Copyright © 2022 Lady [@ Lady’s Computer].
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// 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/>.
+
+export {
+ assert,
+ assertEquals,
+ assertStrictEquals,
+ assertThrows,
+} from "https://deno.land/std@0.134.0/testing/asserts.ts";
--- /dev/null
+// ♓🌟 Piscēs ∷ i·r·i.js
+// ====================================================================
+//
+// Copyright © 2020, 2022 Lady [@ Lady’s Computer].
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// 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/>.
+
+//deno-lint-ignore-file no-unused-vars
+
+const sub·delims = String.raw`[!\$&'()*+,;=]`;
+const gen·delims = String.raw`[:/?#\[\]@]`;
+const reserved = String.raw`${gen·delims}|${sub·delims}`;
+const unreserved = String.raw`[A-Za-z0-9\-\._~]`;
+const pct·encoded = String.raw`%[0-9A-Fa-f][0-9A-Fa-f]`;
+const dec·octet = String.raw
+ `[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5]`;
+const IPv4address = String.raw
+ `(?:${dec·octet})\.(?:${dec·octet})\.(?:${dec·octet})\.(?:${dec·octet})`;
+const h16 = String.raw`[0-9A-Fa-f]{1,4}`;
+const ls32 = String.raw`(?:${h16}):(?:${h16})|${IPv4address}`;
+const IPv6address = String.raw
+ `(?:(?:${h16}):){6}(?:${ls32})|::(?:(?:${h16}):){5}(?:${ls32})|(?:${h16})?::(?:(?:${h16}):){4}(?:${ls32})|(?:(?:(?:${h16}):){0,1}(?:${h16}))?::(?:(?:${h16}):){3}(?:${ls32})|(?:(?:(?:${h16}):){0,2}(?:${h16}))?::(?:(?:${h16}):){2}(?:${ls32})|(?:(?:(?:${h16}):){0,3}(?:${h16}))?::(?:${h16}):(?:${ls32})|(?:(?:(?:${h16}):){0,4}(?:${h16}))?::(?:${ls32})|(?:(?:(?:${h16}):){0,5}(?:${h16}))?::(?:${h16})|(?:(?:(?:${h16}):){0,6}(?:${h16}))?::`;
+const IPvFuture = String.raw
+ `v[0-9A-Fa-f]{1,}\.(?:${unreserved}|${sub·delims}|:)`;
+const IP·literal = String.raw`\[(?:${IPv6address}|${IPvFuture})\]`;
+const port = String.raw`[0-9]*`;
+const scheme = String.raw`[A-Za-z][A-Za-z0-9+\-\.]*`;
+const iprivate = String.raw
+ `[\u{E000}-\u{F8FF}\u{F0000}-\u{FFFFD}\u{100000}-\u{10FFFD}]`;
+const ucschar = String.raw
+ `[\u{A0}-\u{D7FF}\u{F900}-\u{FDCF}\u{FDF0}-\u{FFEF}\u{10000}-\u{1FFFD}\u{20000}-\u{2FFFD}\u{30000}-\u{3FFFD}\u{40000}-\u{4FFFD}\u{50000}-\u{5FFFD}\u{60000}-\u{6FFFD}\u{70000}-\u{7FFFD}\u{80000}-\u{8FFFD}\u{90000}-\u{9FFFD}\u{A0000}-\u{AFFFD}\u{B0000}-\u{BFFFD}\u{C0000}-\u{CFFFD}\u{D0000}-\u{DFFFD}\u{E0000}-\u{EFFFD}]`;
+const iunreserved = String.raw`[A-Za-z0-9\-\._~]|${ucschar}`;
+const ipchar = String.raw
+ `${iunreserved}|${pct·encoded}|${sub·delims}|[:@]`;
+const ifragment = String.raw`(?:${ipchar}|[/?])*`;
+const iquery = String.raw`(?:${ipchar}|${iprivate}|[/?])*`;
+const isegment·nz·nc = String.raw
+ `(?:${iunreserved}|${pct·encoded}|${sub·delims}|@)+`;
+const isegment·nz = String.raw`(?:${ipchar})+`;
+const isegment = String.raw`(?:${ipchar})*`;
+const ipath·empty = String.raw``;
+const ipath·rootless = String.raw
+ `(?:${isegment·nz})(?:/(?:${isegment}))*`;
+const ipath·noscheme = String.raw
+ `(?:${isegment·nz·nc})(?:/(?:${isegment}))*`;
+const ipath·absolute = String.raw
+ `/(?:(?:${isegment·nz})(?:/(?:${isegment}))*)?`;
+const ipath·abempty = String.raw`(?:/(?:${isegment}))*`;
+const ipath = String.raw
+ `${ipath·abempty}|${ipath·absolute}|${ipath·noscheme}|${ipath·rootless}|${ipath·empty}`;
+const ireg·name = String.raw
+ `(?:${iunreserved}|${pct·encoded}|${sub·delims})*`;
+const ihost = String.raw`${IP·literal}|${IPv4address}|${ireg·name}`;
+const iuserinfo = String.raw
+ `(?:${iunreserved}|${pct·encoded}|${sub·delims}|:)*`;
+const iauthority = String.raw
+ `(?:(${iuserinfo})@)?(${ihost})(?::(${port}))?`;
+const irelative·part = String.raw
+ `//(${iauthority})(${ipath·abempty})|(${ipath·absolute})|(${ipath·noscheme})|(${ipath·empty})`;
+const irelative·ref = String.raw
+ `(${irelative·part})(?:\?(${iquery}))?(?:#(${ifragment}))?`;
+const ihier·part = String.raw
+ `//(${iauthority})(${ipath·abempty})|(${ipath·absolute})|(${ipath·rootless})|(${ipath·empty})`;
+const absolute·IRI = String.raw
+ `(${scheme}):(${ihier·part})(?:\?(${iquery}))?`;
+const IRI = String.raw
+ `(${scheme}):(${ihier·part})(?:\?(${iquery}))?(?:#(${ifragment}))?`;
+const IRI·reference = String.raw`(${IRI})|(${irelative·ref})`;
+
+export const isI·R·I = ($) =>
+ typeof $ == "string" && isI·R·I.regExp.test($);
+Object.defineProperty(isI·R·I, "regExp", {
+ configurable: true,
+ enumerable: false,
+ get: () => new RegExp(`^(?:${IRI})$`, "u"),
+});
--- /dev/null
+// ♓🌟 Piscēs ∷ mod.js
+// ====================================================================
+//
+// Copyright © 2020–2022 Lady [@ Lady’s Computer].
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at <https://mozilla.org/MPL/2.0/>.
+
+export * from "./base64.js";
+export * from "./collection.js";
+export * from "./i·r·i.js";
+export * from "./numeric.js";
+export * from "./object.js";
--- /dev/null
+// ♓🌟 Piscēs ∷ numeric.js
+// ====================================================================
+//
+// Copyright © 2022 Lady [@ Lady’s Computer].
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at <https://mozilla.org/MPL/2.0/>.
+
+/** 2^53 − 1. */
+export const MAX_SAFE_INTEGER = Number((1n << 53n) - 1n);
--- /dev/null
+// ♓🌟 Piscēs ∷ object.js
+// ====================================================================
+//
+// Copyright © 2022 Lady [@ Lady’s Computer].
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at <https://mozilla.org/MPL/2.0/>.
+
+/** Returns whether the provided value is a constructor. */
+export const isConstructor = ($) => {
+ if (!isObject($)) {
+ // The provided value is not an object.
+ return false;
+ } else {
+ // The provided value is an object.
+ try {
+ Reflect.construct(
+ function () {},
+ [],
+ $,
+ ); // will throw if $ is not a constructor
+ return true;
+ } catch {
+ return false;
+ }
+ }
+};
+
+/** Returns whether the provided value is an object. */
+export const isObject = ($) => {
+ return $ !== null &&
+ (typeof $ == "function" || typeof $ == "object");
+};
+
+/**
+ * Returns whether the provided object inherits from the prototype of
+ * the provided function.
+ */
+export const ordinaryHasInstance = Function.prototype.call.bind(
+ Function.prototype[Symbol.hasInstance],
+);