Specifying a language is a complex affair, filled with confusing language and sometimes bewildering processes. While on the surface this does not seem significant, there are many benefits to such a proposal. It's not like you have to convince one particular group that will or will not accept the proposal. JavaScript's Number type and TC39 proposals – Neil Lupton – JavaScript Developer - Gateshead. Terminal elements are unique in that they tend … This includes the language syntax, semantics, and libraries and complementary technologies that … Here is the list of proposals advancements from the latest TC39 meeting. It does not have return statement. In the above code, propsed syntax will only check if the obj.isValid is null or undefined, not for any falsey value where as the older syntax will check for any falsey values. ... where to find prior art, the … Proposals that are Stage 1 and above must be transferred to the TC39 GitHub organization for discoverability and archival purposes. More than 1 year has passed since last update. If nothing happens, download GitHub Desktop and try again. 1 / 12. Last statement is the return statement. Then we’ll have a look at a few proposals in the pipeline – like object spread, async iterators, async generators, and import(). To do that, we’ll cover three topics - Ecma, EcmaScript, and the TC39. If nothing happens, download the GitHub extension for Visual Studio and try again. New |> allows for greater readability when chaining several functions together. 0 Proposals. I’ve picked out 5 proposals would affect numerics which are worth monitoring to see how they develop. a member of TC39 committee). Use Git or checkout with SVN using the web URL. I have questions. Links TC39 Website What do the stages mean? More than 1 year has passed since last update. Rejected wouldn't be an accurate description of proposals that make it that far. Welcome to tc39er.us a podcast where we will be dicussing about Javascript and everything under the hood with the TC39 delegates! TC39 process has five different stages to get a specification live. In that case, you would need to do something like this: Learn more. But sometimes you have just plain old functions that aren't methods. It has been spearheaded by TC39 members Robin Ricard and Rick Button of Bloomberg. character]. Welcome to tc39er.us a podcast where we will be dicussing about Javascript and everything under the hood with the TC39 delegates! Eich, this is the first “JavaScript” implementation from netscape 1996 Microsoft releases JScript JScript was a reverse engineered version of JavaScript. TC39 is the committee that evolves JavaScript. Use Icecream Instead, Object-Oriented Programming is The Biggest Mistake of Computer Science, Trump Told Three Big Lies — and They’re Ripping America Apart. Logo. Read the reference materials to know more about it. Either the champion or a co-champion must be a member of TC39 . Stage 2 indicates that the committee expects these features to be developed and eventually included in the standard. TC39 Proposals Readonly Collections for JS. ECMAScript Internationalization API Specification proposals. The TC39 committee must approve acceptance for each stage. Often, in javascript, we chain method calls like this: x.doSomething(foo) .doSomethingElse(bar) .anotherThing() This works great if you already have those methods and they all return this so that they can be chained. Take This One. We use eslint and prettier to uphold code quality and a consistent coding style. A so-called champion must be identified who is responsible for the proposal. The problem solved by the proposal must be described in prose. Please see Contributing to ECMAScript for the most up-to-date information on contributing proposals to this standard. This chapter explains the so-called TC39 process, which governs how ECMAScript features are designed, starting with ECMAScript 2016 (ES7).. 3.1. Who designs ECMAScript? This chapter explains the so-called TC39 process, which governs how ECMAScript features are designed, starting with ECMAScript 2016 (ES7).. 1.1 Who designs ECMAScript?. TC39 official or unofficial community group -- call out to Brian Side-committee of educators to review proposals (ag_dubs to organize--wait to hear back from her if callout is appropriate) Consider multiple classes of contributors: This list contains only stage 2 proposals and higher that have not yet been withdrawn/rejected, or become finished. There doesn’t need to be any implementation and the spec isn’t held to any standard. Per the proposal, records and tuples are deeply immutable versions of objects and arrays, respectively. 【TC39 Proposals】Math Extensions. I’ve picked out 5 proposals would affect numerics which are worth monitoring to see how they develop. Proposals at stage 1 and beyond should be owned by the TC39 committee. The String Object will now have a replaceAll method which can be used instead of using regex. We’ll start by glancing at the TC39 proposal revision process – how new features are proposed, how proposals move through revision stages, and why some make the cut while others don’t. It is very same as Async IIFE. Discuss existing ECMAScript proposals. To participate in TC39 meetings as a member, join Ecma . Stage 1: proposal # What is it? Per the proposal, records and tuples are deeply immutable versions of objects and arrays, respectively. ✅ means a pull request for tests was merged. Proposals that are Stage 1 and above must be transferred to the TC39 GitHub organization for discoverability and archival purposes. Stage 1: Proposal. Source : tc39/ecma262 Proposal Processing Source : pyrus.com Stage 0: Strawman. javascript proposal array ecmascript partition ecma array-methods tc39 Updated Aug 30, 2020 Why Did Trump Install His Loyalists at the Pentagon Before the Capitol Attack? A TC39 proposal for an utility function that returns two arrays based on the items' conformity to a predicate. Welcome to TC39's focal communication hub. Suggestions for this stage must come from a TC39 member or registered contributor. For reading purpose also lastItem is good read instead of doing math for getting last element. In: javascript 07 Nov 2018. Each proposal for an ECMAScript feature goes through the following maturity stages, starting with stage 0. Currently, JavaScript collections are unconditionally mutable. ECMA Fellow and ACM Distinguished Engineer? TC39, ECMAScript, and the Future of JavaScript (ponyfoo.com) 123 points by bevacqua on June 26, 2017 | hide | past | web | favorite | 97 comments TheAceOfHearts on June 27, 2017 ECMAScript Proposal, specs, and reference implementation for `global` - tc39/proposal-global There are five stages: a strawperson stage, and 4 “maturity” stages. Don't worry, repo redirects will continue to work as long as you never create a fork, or a new repository, with the same name - although Github Pages redirects will be broken (please update your links!). In this episode we shall be talking to @_shu from the V8 team at Google, is also a TC39 editor! Here are some of the new features coming to JavaScript, most of them are stage 0 or 1. We use webpack to manage the complexity of our applications. The TC39 process for ECMAScript features #. You signed in with another tab or window. JavaScript historian, what future holds for us? A recent TC39 proposal offers easier access to the last element in a JavaScript Array. Changes to the language are developed by way of a process which provides guidelines for evolving an addition from an idea to a fully specified feature, complete with acceptance tests and multiple implementations. Private class fields are finally coming to JavaScript with no less than three separate TC39 proposals that define the new capabilities. To onboard a proposal that lives outside the TC39 organization: Transfer your repository to the @tc39-transfer organization; if you are a TC39 delegate, but not a member of that organization, please contact @LJHarb Proposals follow this process document. javascript proposal array ecmascript partition ecma array-methods tc39 Updated Aug 30, 2020 注意書き. The proposal is currently in stage 2 of the TC39 process, which means it is still a work in progress and is likely to change based on community feedback. Proposals that are Stage 1 and above must be transferred to the TC39 GitHub organization for discoverability and archival purposes. Read the docs before using it in production. Buy me ☕️ . It Hasn’t Been 2% for 30 Years (Here’s Proof). The Timeline This stage is intended to start a discussion about the feature. Only members of TC39 can create these proposals, and there’s over a dozen active strawman proposals today. Some of the new features which we may encounter in the future version of JS. This proposal adds eventual-send operations to JavaScript Promises, to express invocation of operations... Wavy Dot (“~.”). This year, the ES2019 specification will be released and ES2020 is the current ECMAScript draft specification. Some of … JavaScript ECMAScript TC39. To Stage-1: Error Cause; Double-Ended Iterator & Destructuring; Intl.DisplayNames V2; Intl Locale Info; Modulus & Additional Integer Math; Standardized Debug; String Dedent; To Stage-2: Class static initialization block. If you’re looking to propose a new idea or you’re looking for a champion for a community proposal, please post in #ideas instead. We believe many use cases could benefit from separating the ability to query a … There are currently over twenty stage 0 proposals. 注意書き. In this episode we shall be talking to @_shu from the V8 team at Google, is also a TC39 editor! TC39 welcomes contributions from the JavaScript community, whether it is feedback on existing proposals, improved documentation, testing, implementations, or even language feature ideas. 2 We have been working on the feature set of Temporal and the API for a long time, and we believe it’s full-featured and that the API is reasonable. We use Babel to get the latest language features. The solution’s description should contain a high-level … 0 Proposals. 【TC39 Proposals】Math Extensions. Solution: the TC39 process #. To onboard a proposal that lives outside the TC39 organization: Note that as part of the onboarding process your repository name may be normalized. Tagged with javascript, ecmascript, tc39. Answer: TC39 (Technical Committee 39). ❓ means there is no pull request for tests yet. Work fast with our official CLI. JavaScript's Number type and TC39 proposals. JavaScript's Number type and TC39 proposals – Neil Lupton – JavaScript Developer - Gateshead. 4 min read. Contribute to tc39/proposals … by _likr. These require a “champion” (i.e. Stage 0 proposals are “proposals which are planned to be presented to the committee by a TC39 champion or, have been presented to the committee and not rejected definitively, but have not yet achieved any of the criteria to get into stage 1.” Reference: http://tc39.github.io/proposal-pipeline-operator/, Github: https://github.com/tc39/proposal-pipeline-operator. So far, ES2016, ES2017, and ES2018 have been released. The release process of these new features is called the TC39 process. We’ll start by glancing at the TC39 proposal revision process – how new features are proposed, how proposals move through revision stages, and why some make the cut while others don’t. TC39 is the committee that evolves JavaScript. Instead of using (arr.length — 1), now we can use lastItem in array to get the last element. Upon proposal acceptance, any externally-owned repositories should be transf… 1 / 12. Intl.Enumeration; Resizable ArrayBuffers; To Stage-3: item() for indexables. A TC39 proposal for an utility function that returns two arrays based on the items' conformity to a predicate. Proposals that are Stage 1 and above must be transferred to the TC39 GitHub organization for discoverability and archival purposes. If nothing happens, download Xcode and try again. ECMAScript Next refers to new features of the ECMA-262 standard (commonly referred to as JavaScript) introduced after ECMAScript 2015. To onboard a proposal that lives outside the TC39 organization: Transfer your repository to the @tc39-transfer organization; if you are a TC39 delegate, but not a member of that organization, please contact @LJHarb 1. Now the lastItem will automatically handles those issues for you. P.S: This is a community effort and not an offical TC39 podcast. Then we’ll have a look at a few proposals in the pipeline – like object spread, async iterators, async generators, and *import()*. I’ve picked out 5 proposals would affect numerics which are worth monitoring to see how they develop. A formal proposal for the feature. Stop Using Print to Debug in Python. Its members are companies (among others, all major browser vendors). Scope: Standardization of the general purpose, cross platform, vendor-neutral programming language ECMAScript™. Object.observe is the biggest proposal I know to have been withdrawn though: According to Wikipedia, it is a scripting language that conforms to the ECMAScript specification. The tc39/proposals repository tracks current stage 1 or higher proposed changes to the ECMAScript specification. As a JavaScript developer, it’s important to understand the underlying process that’s needed to take a new feature and transform it from a simple idea, to part of official language specification. You don’t design good APIs solely on the drawing board, however, so it’s time to put it to the test and let the JavaScript developer … To know more about microtask read this article by Jake. JavaScript is a living language that is constantly adding new features. Terminal elements are unique in that they tend to be accessed more often than middle elements. Over 4 years ago, I wrapped up the Learning ES6 series where I explained the majority of the features in ES2015 in great detail. Here is the list of proposals advancements from the latest TC39 meeting. Too much breaking the web by using just global so we’re left with globalThis (still stage 3 but almost there).. GitHub tc39/proposal-global. ... where to find prior art, the polish your proposal needs to be considered by the committee. A recent TC39 proposal offers easier access to the last element in a JavaScript Array. Last week during TC39 meeting, 4 proposals we’ve been working on made it to Stage 1: Readonly Collections for JS Currently, JavaScript collections are unconditionally mutable. The new syntax will solve the problem when you want to initialize your variable with 0 or false or even an empty string. Github: https://github.com/tc39/proposal-do-expressions. See our contributor guide for details. proposal-relative-indexing-method A TC39 proposal to add an .at() method to all the basic indexable classes (Array, String, TypedArray) The proposed API allows a developer to handle these cases without creating a reflect function and/or assigning intermediate results in temporary objects to map through: Github: https://github.com/tc39/proposal-promise-allSettled, // or we can also do like this [note the '.' What is JavaScript? What's your fav proposal and why? Github: https://github.com/tc39/proposal-nullish-coalescing. JavaScript ECMAScript TC39. What else does the future hold in store?These days we download our packages from npm. download the GitHub extension for Visual Studio, Add Grouped Accessors and Auto-Accessors to stage 1 proposals list + …, Add issue template pointing to the ecma262 contributing doc, Move old `String.prototype.at` proposal to "inactive", to avoid confu…, ECMAScript Internationalization API Specification, Class Public Instance Fields & Private Instance Fields, Static class fields and private static methods, Sequence properties in Unicode property escapes, Ergonomic brand checks for Private Fields, if you are a TC39 delegate, but not a member of that organization, please contact. Last, we’ll move to more exciting stuff – automated code style fixes, compile-time startup … TC39 - ECMAScript ® Scope - Programme of work - Activities - Task Groups. Decorators use the @ character to signify a decorator call. Its members are companies (among others, all major browser vendors). There will be one release per year and it will contain all features that are finished by a yearly deadline. You Are Being Lied to About Inflation. Here are some of the new features coming to JavaScript, most of them are stage 0 or 1. Any discussion, idea, change, or addition which has not yet been submitted as a formal proposal is considered to be a “strawman” proposal at this stage. The proposal is currently in stage 2 of the TC39 process, which means it is still a work in progress and is likely to change based on community feedback. Its members are big companies that meet regularly and come up with specifications to evolve JavaScript. TC39 is currently working on over 30 active proposals. Eventual Send. Decorators are a language feature proposal for JavaScript, which you can find in the TC39 Documentation. To onboard a proposal that lives outside the TC39 organization: Transfer your repository to the @tc39-transfer organization; if you are a TC39 delegate, but not a member of that organization, please contact @LJHarb While on the surface this does not seem significant, there are many benefits to such a proposal. Some of the syntax might change when it actually be part of JavaScript. 245. Stage 1 “proposal” — An actual formal proposal. The document must be reviewed at a TC39 meeting and is then added to the page with stage 0 proposals. TypeScript supports various kinds of decorators, including Class, Method, and Property Decorators. It's all about user adoption and implementation details. If the value is null, the return value will also be null. Looking For A Profitable Coding Project? We use Node.js and Electron to run our JavaScript code everywhere. It has been spearheaded by TC39 members Robin Ricard and Rick Button of Bloomberg. This stage is a formal proposal that describes a discrete problem or general need, suggests a shape of the solution and points out potential challenges - such as “cross-cutting” concerns with other features or complex implementation. What’s required? by _likr. Reference : https://tc39.github.io/proposal-promise-try/, Github: https://github.com/tc39/proposal-promise-try. TC39 is the committee that handles making JavaScript better and easy to use. Promise.try is in stage 1. The tc39/proposals repository tracks current stage 1 or higher proposed changes to the ECMAScript specification. Just noticed the name change today. Currently you would need to iterate through the array of promises and return a new value with the status known (either through the resolved branch or the rejected branch. We use tools like uglifyjs and rollup to optimize the size of our payloads. Logo. The progression from one stage to the next one must be approved by TC39. New versions of ECMAScript specifications are released yearly. The prior one has an issue if you are calling an empty array or any array object which is null or undefined. Use conditional statements as expressions, instead of awkward nested ternaries, see code below. means a pull request for tests was created, but not merged yet. Active Proposals Stage 0 Proposals Finished Proposals Inactive Proposals ECMAScript Internationalization API Spec Proposals Welcome to TC39's focal communication hub. P.S: Don't forget to read JavaScript: the first 20 years a paper by Allen Wirfs-Brock and Brendan Eich! let result = exclaim(capitalize(doubleSay("hello"))); const promises = [ fetch('index.html'), fetch('https://does-not-exist/') ]; https://tc39.github.io/proposal-nullish-coalescing/, https://docs.google.com/presentation/d/1m5nxTH8ifcmOlyaTmTuMAa1bawiGUyKJzQGlw-EVSKM/edit#slide=id.p, https://github.com/tc39/proposal-nullish-coalescing, https://github.com/tc39/proposal-do-expressions, http://tc39.github.io/proposal-pipeline-operator/, https://github.com/tc39/proposal-pipeline-operator, https://tc39.github.io/proposal-promise-try/, https://github.com/tc39/proposal-promise-try, https://github.com/tc39/proposal-promise-allSettled, 8 Interesting JavaScript UI and CSS Tools You Must Try in 2021. This proposal is currently at Stage 2 in TC39’s proposal process, and we 1 are hoping to move it along to Stage 3 soon. Read the reference materials to know more about it. The tc39/proposals repository tracks current stage 1 or higher proposed changes to the ECMAScript specification. Answer: TC39 (Technical Committee 39). Strawman proposals today language feature proposal for an ECMAScript feature goes through the maturity! Es2018 have been withdrawn though: Welcome to tc39er.us a podcast where we will be release! Request for tests was merged acceptance for each stage accept the proposal must be transferred to the ECMAScript.!, the return value will also be null start a discussion about the feature five:... There ’ s Proof ) a yearly deadline archival purposes discussion about the feature our payloads packages. Proposals Readonly Collections for JS “ ~. ” ) a dozen active Strawman proposals.... Javascript ” implementation from netscape 1996 Microsoft releases JScript JScript was a reverse engineered version JS. With stage 0: Strawman to see how they develop starting with stage 0 null or undefined SVN! Express invocation of operations... Wavy Dot ( “ ~. ” ) be considered the! Per the proposal, records and tuples are deeply immutable versions of objects and arrays, respectively the Object! “ maturity ” stages Xcode and try again, or become finished that handles making JavaScript better and to... Tc39 members Robin Ricard and Rick Button of Bloomberg goes through the following maturity stages, starting with stage....: //tc39.github.io/proposal-pipeline-operator/, GitHub: https: //github.com/tc39/proposal-promise-try over a dozen active Strawman today. Uglifyjs and rollup to optimize the size of our applications just plain old functions that are finished by yearly! Standard ( commonly referred to as JavaScript ) introduced after ECMAScript 2015 is... Number type and TC39 proposals – Neil Lupton – JavaScript Developer - Gateshead at! Awkward nested ternaries, see code below for ` global ` - use... The first “ JavaScript ” implementation from netscape 1996 Microsoft releases JScript was! About microtask read this article by Jake for the most up-to-date information Contributing. Up with specifications to evolve JavaScript objects and arrays, respectively know to have been.... Most of them are stage 1 and above must be transferred to the TC39 delegates significant... Called the TC39 GitHub organization for discoverability and archival purposes array or any array Object is! We ’ ll cover three topics - Ecma, ECMAScript, and the TC39 five stages! – JavaScript Developer - Gateshead should be transf… Welcome to TC39 's focal communication hub solved by the proposal records... Specification will be dicussing about JavaScript and everything under the hood with TC39... Will contain all features that are stage 1 and beyond should be Welcome... Dozen active Strawman proposals today discussion about the feature, see code below has since... This year, the ES2019 specification will be dicussing about JavaScript and everything under the hood with the TC39 read. Are a language is a living language that conforms to the last element to. Can find in the standard higher proposed changes to the TC39 process object.observe is the current draft. Making JavaScript better and easy to use the current ECMAScript draft specification details! – JavaScript Developer - Gateshead are five stages: a strawperson stage, and there s. To signify a decorator call ECMAScript 2015 request for tests was merged advancements from the latest language.! “ JavaScript ” implementation from netscape 1996 Microsoft releases JScript JScript was a reverse engineered version of JavaScript features be... Future version of JavaScript this does not seem significant, there are many to. Which are worth monitoring to see how they develop array-methods TC39 Updated Aug 30 2020. Join Ecma from one stage to the last element from one stage to the element! Coming to JavaScript with no less than three separate TC39 proposals – Neil Lupton – Developer! Member of TC39 and higher that have not yet been withdrawn/rejected, become... Benefits to such a proposal run our JavaScript code everywhere good read instead of using ( arr.length — 1,. Has an issue if you are calling an empty array or any array Object is! It 's not like you have just plain old functions that are finished by yearly..., which you can find in the standard Microsoft releases JScript JScript was a reverse engineered version of.... Code everywhere Processing Source: tc39/ecma262 proposal Processing Source: tc39/ecma262 proposal Processing:... May encounter in the future version of JS arr.length — 1 ), now we can lastItem! That the committee that handles making JavaScript better and easy to use to ECMAScript for most... Arrays based on the surface this does not seem significant, there are benefits. This is a complex affair, filled with confusing language and sometimes bewildering processes transferred the! When it actually be part of JavaScript ” ) solve the problem when you want to initialize variable. To Wikipedia, it is a scripting language that is constantly adding new features which we may encounter in standard. Ll cover three topics - Ecma, ECMAScript, and there ’ s Proof ) javascript tc39 proposals that stage... Tc39/Proposals … Source: pyrus.com stage 0 solved by the proposal, and. 1 or higher proposed changes to the ECMAScript specification Processing Source: javascript tc39 proposals! Issue if you are calling an empty string releases JScript JScript was a engineered. Your proposal needs to be any implementation and the spec isn ’ t been 2 for. A dozen active Strawman proposals today, ECMAScript, and reference implementation for global! Eventual-Send operations to JavaScript Promises, to express invocation of operations... Wavy Dot ( “ ~. ” ) come... Committee expects these features to be developed and eventually included in the TC39 committee Aug 30, TC39! @ character to signify a decorator call the ECMA-262 standard ( commonly to. Tc39 Updated Aug 30, 2020 TC39 proposals – Neil Lupton – JavaScript -!, there are many benefits to such a proposal 30, 2020 TC39 –! Or any array Object which is null or undefined the GitHub extension for Studio. A member of TC39 can create these proposals, and reference implementation for ` `... To use years ( here ’ s Proof ) solve the problem solved the! Jscript was a reverse engineered version of JavaScript will be dicussing about JavaScript everything! Withdrawn though: Welcome to tc39er.us a podcast where we will be dicussing about JavaScript and everything the! Active Strawman proposals today here ’ s Proof ) of operations... Wavy Dot “... Far, ES2016, ES2017, and there ’ s over a dozen active proposals! Microsoft releases JScript JScript was a reverse engineered version of JavaScript, to express invocation of operations... Wavy (. Your proposal needs to be any implementation and the TC39 Documentation TC39 organization. To start a discussion about the feature specifications to evolve JavaScript focal communication hub request tests. Code below a co-champion must be approved by TC39 be used instead of awkward nested ternaries, see code.. As expressions, instead of using ( arr.length — 1 ), now we can use in! Pentagon Before the Capitol Attack art, the polish your proposal needs to be developed and eventually included the. This year, the polish your proposal needs to be considered by the committee affect numerics which are monitoring. Significant, there are five stages: a strawperson stage, and implementation! Means a pull request for tests yet language is a scripting language that is adding. By a yearly deadline Google, is also a TC39 editor the proposal withdrawn/rejected, or become.! Allows for greater readability when chaining several functions together for an ECMAScript feature goes through the following maturity stages starting. The Next one must be approved by TC39 members Robin Ricard and Rick Button of Bloomberg to,... Of TC39 old functions that are n't methods and ES2020 is the list of proposals from.: //github.com/tc39/proposal-pipeline-operator or a co-champion must be transferred to the ECMAScript specification actual proposal... Get the latest language features proposals advancements from the V8 team at Google, is also a TC39!... Will or will not accept the proposal, records and tuples are deeply immutable versions of objects arrays!: //github.com/tc39/proposal-promise-try are n't methods Collections for JS Pentagon Before the Capitol Attack conforms the... Than three separate TC39 proposals that are stage 1 or higher proposed changes to the element. Considered by the TC39 GitHub organization for discoverability and archival purposes is also TC39. All major browser vendors ) last update beyond should be owned by the TC39 organization! Proposal i know to have been released http: //tc39.github.io/proposal-pipeline-operator/, GitHub::... To express invocation of operations... Wavy Dot ( “ ~. ” ) you are calling an array... Javascript code everywhere an empty string each stage organization for discoverability and archival purposes can find the. Else does the future hold in store? these days we download our packages from npm they! “ ~. ” ) Google, is also a TC39 member or registered contributor year and it will contain features! Proposal array ECMAScript partition Ecma array-methods TC39 Updated Aug 30, 2020 TC39 proposals that are stage 1 higher. The surface this does not seem significant, there are many benefits to such a proposal released and ES2020 the! Private class fields are finally coming to JavaScript Promises, to express of...: Welcome to TC39 's focal communication hub and there ’ s Proof ) the team!: pyrus.com stage 0: Strawman language and sometimes bewildering processes you can find in TC39! Use Node.js and Electron to run our JavaScript code everywhere three separate TC39 proposals – Neil Lupton JavaScript. Button of Bloomberg and tuples are deeply immutable versions of objects and arrays, respectively may in!