jashkenas--coffeescript/documentation/sections/changelog.md

Changelog

releaseHeader('2017-09-17', '2.0.0', '2.0.0-beta5')

• Added --transpile flag or transpile Node API option to tell the CoffeeScript compiler to pipe its output through Babel before saving or returning it; see Transpilation. Also changed the -t short flag to refer to --transpile instead of --tokens.
• Always populate source maps’ sourcesContent property.
• Bugfixes for destructuring and for comments in JSX.
• Note that these are only the changes between 2.0.0-beta5 and 2.0.0. See below for all changes since 1.x.

releaseHeader('2017-09-02', '2.0.0-beta5', '2.0.0-beta4')

• Node 6 is now supported, and we will try to maintain that as the minimum required version for CoffeeScript 2 via the coffee command or Node API. Older versions of Node, or non-evergreen browsers, can compile via the browser compiler.
• The command line --output flag now allows you to specify an output filename, not just an output folder.
• The command line --require flag now properly handles filenames or module names that are invalid identifiers (like an NPM module with a hyphen in the name).
• Object.assign, output when object destructuring is used, is polyfilled using the same polyfill that Babel outputs. This means that polyfills shouldn’t be required unless support for Internet Explorer 8 or below is desired (or your own code uses a feature that requires a polyfill). See ES2015+ Output.
• A string or JSX interpolation that contains only a comment ("a#{### comment ###}b" or <div>{### comment ###}</div>) is now output (`a${/* comment */}b`)
• Interpolated strings (ES2015 template literals) that contain quotation marks no longer have the quotation marks escaped: `say "${message}"`
• It is now possible to chain after a function literal (for example, to define a function and then call .call on it).
• The results of the async tests are included in the output when you run cake test.
• Bugfixes for object destructuring; expansions in function parameters; generated reference variables in function parameters; chained functions after do; splats after existential operator soaks in arrays ([a?.b...]); trailing if with splat in arrays or function parameters ([a if b...]); attempting to throw an if, for, switch, while or other invalid construct.
• Bugfixes for syntactical edge cases: semicolons after = and other “mid-expression” tokens; spaces after ::; and scripts that begin with : or *.
• Bugfixes for source maps generated via the Node API; and stack trace line numbers when compiling CoffeeScript via the Node API from within a .coffee file.

releaseHeader('2017-08-03', '2.0.0-beta4', '2.0.0-beta3')

• This release includes all the changes from 1.12.6 to 1.12.7.
• Line comments (starting with #) are now output in the generated JavaScript.
• Block comments (delimited by ###) are now allowed anywhere, including inline where they previously weren’t possible. This provides support for static type annotations using Flow’s comments-based syntax.
• Spread syntax (... for objects) is now supported in JSX tags: <div {props...} />.
• Argument parsing for scripts run via coffee is improved. See breaking changes.
• CLI: Propagate SIGINT and SIGTERM signals when node is forked.
• await in the REPL is now allowed without requiring a wrapper function.
• do super is now allowed, and other accesses of super like super.x.y or super['x'].y now work.
• Splat/spread syntax triple dots are now allowed on either the left or the right (so props... or ...props are both valid).
• Tagged template literals are recognized as callable functions.
• Bugfixes for object spread syntax in nested properties.
• Bugfixes for destructured function parameter default values.

releaseHeader('2017-07-16', '1.12.7', '1.12.6')

• Fix regressions in 1.12.6 related to chained function calls and indented return and throw arguments.
• The REPL no longer warns about assigning to _.

releaseHeader('2017-06-30', '2.0.0-beta3', '2.0.0-beta2')

• JSX is now supported.
• Object rest/spread properties are now supported.
• Bound (fat arrow) methods are once again supported in classes; though an error will be thrown if you attempt to call the method before it is bound. See breaking changes for classes.
• The REPL no longer warns about assigning to _.
• Bugfixes for destructured nested default values and issues related to chaining or continuing expressions across multiple lines.

releaseHeader('2017-05-16', '2.0.0-beta2', '2.0.0-beta1')

• This release includes all the changes from 1.12.5 to 1.12.6.
• Bound (fat arrow) methods in classes must be declared in the class constructor, after super() if the class is extending a parent class. See breaking changes for classes.
• All unnecessary utility helper functions have been removed, including the polyfills for indexOf and bind.
• The extends keyword now only works in the context of classes; it cannot be used to extend a function prototype. See breaking changes for extends.
• Literate CoffeeScript is now parsed entirely based on indentation, similar to the 1.x implementation; there is no longer a dependency for parsing Markdown. See breaking changes for Literate CoffeeScript parsing.
• JavaScript reserved words used as properties are no longer wrapped in quotes.
• require('coffeescript') should now work in non-Node environments such as the builds created by Webpack or Browserify. This provides a more convenient way to include the browser compiler in builds intending to run in a browser environment.
• Unreachable break statements are no longer added after switch cases that throw exceptions.
• The browser compiler is now compiled using Babili and transpiled down to Babel’s env preset (should be safe for use in all browsers in current use, not just evergreen versions).
• Calling functions @get or @set no longer throws an error about required parentheses. (Bare get or set, not attached to an object or @, still intentionally throws a compiler error.)
• If $XDG_CACHE_HOME is set, the REPL .coffee_history file is saved there.

releaseHeader('2017-05-15', '1.12.6', '1.12.5')

• The return and export keywords can now accept implicit objects (defined by indentation, without needing braces).
• Support Unicode code point escapes (e.g. \u{1F4A9}).
• The coffee command now first looks to see if CoffeeScript is installed under node_modules in the current folder, and executes the coffee binary there if so; or otherwise it runs the globally installed one. This allows you to have one version of CoffeeScript installed globally and a different one installed locally for a particular project. (Likewise for the cake command.)
• Bugfixes for chained function calls not closing implicit objects or ternaries.
• Bugfixes for incorrect code generated by the ? operator within a termary if statement.
• Fixed some tests, and failing tests now result in a nonzero exit code.

releaseHeader('2017-04-14', '2.0.0-beta1', '2.0.0-alpha1')

• Initial beta release of CoffeeScript 2. No further breaking changes are anticipated.
• Destructured objects and arrays now output using ES2015+ syntax whenever possible.
• Literate CoffeeScript now has much better support for parsing Markdown, thanks to using Markdown-It to detect Markdown sections rather than just looking at indentation.
• Calling a function named get or set now requires parentheses, to disambiguate from the get or set keywords (which are disallowed).
• The compiler now requires Node 7.6+, the first version of Node to support asynchronous functions without requiring a flag.

releaseHeader('2017-04-10', '1.12.5', '1.12.4')

• Better handling of default, from, as and * within import and export statements. You can now import or export a member named default and the compiler won’t interpret it as the default keyword.
• Fixed a bug where invalid octal escape sequences weren’t throwing errors in the compiler.

releaseHeader('2017-02-21', '2.0.0-alpha1', '1.12.4')

• Initial alpha release of CoffeeScript 2. The CoffeeScript compiler now outputs ES2015+ syntax whenever possible. See breaking changes.
• Classes are output using ES2015 class and extends keywords.
• Added support for async/await.
• Bound (arrow) functions now output as => functions.
• Function parameters with default values now use ES2015 default values syntax.
• Splat function parameters now use ES2015 spread syntax.
• Computed properties now use ES2015 syntax.
• Interpolated strings (template literals) now use ES2015 backtick syntax.
• Improved support for recognizing Markdown in Literate CoffeeScript files.
• Mixing tabs and spaces in indentation is now disallowed.
• Browser compiler is now minified using the Google Closure Compiler (JavaScript version).
• Node 7+ required for CoffeeScript 2.

releaseHeader('2017-02-18', '1.12.4', '1.12.3')

• The cake commands have been updated, with new watch options for most tasks. Clone the CoffeeScript repo and run cake at the root of the repo to see the options.
• Fixed a bug where exporting a referenced variable was preventing the variable from being declared.
• Fixed a bug where the coffee command wasn’t working for a .litcoffee file.
• Bugfixes related to tokens and location data, for better source maps and improved compatibility with downstream tools.

releaseHeader('2017-01-24', '1.12.3', '1.12.2')

• @ values can now be used as indices in for expressions. This loosens the compilation of for expressions to allow the index variable to be an @ value, e.g. do @visit for @node, @index in nodes. Within @visit, the index of the current node (@node) would be available as @index.
• CoffeeScript’s patched Error.prepareStackTrace has been restored, with some revisions that should prevent the erroneous exceptions that were making life difficult for some downstream projects. This fixes the incorrect line numbers in stack traces since 1.12.2.
• The //= operator’s output now wraps parentheses around the right operand, like the other assignment operators.

releaseHeader('2016-12-16', '1.12.2', '1.12.1')

• The browser compiler can once again be built unminified via MINIFY=false cake build:browser.
• The error-prone patched version of Error.prepareStackTrace has been removed.
• Command completion in the REPL (pressing tab to get suggestions) has been fixed for Node 6.9.1+.
• The [browser-based tests](/v<%= majorVersion %>/test.html) now include all the tests as the Node-based version.

releaseHeader('2016-12-07', '1.12.1', '1.12.0')

• You can now import a module member named default, e.g. import { default } from 'lib'. Though like in ES2015, you cannot import an entire module and name it default (so import default from 'lib' is not allowed).
• Fix regression where from as a variable name was breaking for loop declarations. For the record, from is not a reserved word in CoffeeScript; you may use it for variable names. from behaves like a keyword within the context of import and export statements, and in the declaration of a for loop; though you should also be able to use variables named from in those contexts, and the compiler should be able to tell the difference.

releaseHeader('2016-12-04', '1.12.0', '1.11.1')

• CoffeeScript now supports ES2015 tagged template literals. Note that using tagged template literals in your code makes you responsible for ensuring that either your runtime supports tagged template literals or that you transpile the output JavaScript further to a version your target runtime(s) support.
• CoffeeScript now provides a for…from syntax for outputting ES2015 for…of. (Sorry they couldn’t match, but we came up with for…of first for something else.) This allows iterating over generators or any other iterable object. Note that using for…from in your code makes you responsible for ensuring that either your runtime supports for…of or that you transpile the output JavaScript further to a version your target runtime(s) support.
• Triple backticks ( ```​) allow the creation of embedded JavaScript blocks where escaping single backticks is not required, which should improve interoperability with ES2015 template literals and with Markdown.
• Within single-backtick embedded JavaScript, backticks can now be escaped via \`​.
• The browser tests now run in the browser again, and are accessible [here](/v<%= majorVersion %>/test.html) if you would like to test your browser.
• CoffeeScript-only keywords in ES2015 imports and exports are now ignored.
• The compiler now throws an error on trying to export an anonymous class.
• Bugfixes related to tokens and location data, for better source maps and improved compatibility with downstream tools.

releaseHeader('2016-10-02', '1.11.1', '1.11.0')

• Bugfix for shorthand object syntax after interpolated keys.
• Bugfix for indentation-stripping in """ strings.
• Bugfix for not being able to use the name “arguments” for a prototype property of class.
• Correctly compile large hexadecimal numbers literals to 2e308 (just like all other large number literals do).

releaseHeader('2016-09-24', '1.11.0', '1.10.0')

• CoffeeScript now supports ES2015 import and export syntax.

• Added the -M, --inline-map flag to the compiler, allowing you embed the source map directly into the output JavaScript, rather than as a separate file.

• A bunch of fixes for yield:

  • yield return can no longer mistakenly be used as an expression.

  • yield now mirrors return in that it can be used stand-alone as well as with expressions. Where you previously wrote yield undefined, you may now write simply yield. However, this means also inheriting the same syntax limitations that return has, so these examples no longer compile:

    doubles = ->
      yield for i in [1..3]
        i * 2
    six = ->
      yield
        2 * 3
    

  • The JavaScript output is a bit nicer, with unnecessary parentheses and spaces, double indentation and double semicolons around yield no longer present.

• &&=, ||=, and= and or= no longer accidentally allow a space before the equals sign.

• Improved several error messages.

• Just like undefined compiles to void 0, NaN now compiles into 0/0 and Infinity into 2e308.

• Bugfix for renamed destructured parameters with defaults. ({a: b = 1}) -> no longer crashes the compiler.

• Improved the internal representation of a CoffeeScript program. This is only noticeable to tools that use CoffeeScript.tokens or CoffeeScript.nodes. Such tools need to update to take account for changed or added tokens and nodes.

• Several minor bug fixes, including:

  • The caught error in catch blocks is no longer declared unnecessarily, and no longer mistakenly named undefined for catch-less try blocks.
  • Unassignable parameter destructuring no longer crashes the compiler.
  • Source maps are now used correctly for errors thrown from .coffee.md files.
  • coffee -e 'throw null' no longer crashes.
  • The REPL no longer crashes when using .exit to exit it.
  • Invalid JavaScript is no longer output when lots of for loops are used in the same scope.
  • A unicode issue when using stdin with the CLI.

releaseHeader('2015-09-03', '1.10.0', '1.9.3')

• CoffeeScript now supports ES2015-style destructuring defaults.

• (offsetHeight: height) -> no longer compiles. That syntax was accidental and partly broken. Use ({offsetHeight: height}) -> instead. Object destructuring always requires braces.

• Several minor bug fixes, including:

  • A bug where the REPL would sometimes report valid code as invalid, based on what you had typed earlier.
  • A problem with multiple JS contexts in the jest test framework.
  • An error in io.js where strict mode is set on internal modules.
  • A variable name clash for the caught error in catch blocks.

releaseHeader('2015-05-27', '1.9.3', '1.9.2')

• Bugfix for interpolation in the first key of an object literal in an implicit call.
• Fixed broken error messages in the REPL, as well as a few minor bugs with the REPL.
• Fixed source mappings for tokens at the beginning of lines when compiling with the --bare option. This has the nice side effect of generating smaller source maps.
• Slight formatting improvement of compiled block comments.
• Better error messages for on, off, yes and no.

releaseHeader('2015-04-15', '1.9.2', '1.9.1')

• Fixed a watch mode error introduced in 1.9.1 when compiling multiple files with the same filename.
• Bugfix for yield around expressions containing this.
• Added a Ruby-style -r option to the REPL, which allows requiring a module before execution with --eval or --interactive.
• In <script type="text/coffeescript"> tags, to avoid possible duplicate browser requests for .coffee files, you can now use the data-src attribute instead of src.
• Minor bug fixes for IE8, strict ES5 regular expressions and Browserify.

releaseHeader('2015-02-18', '1.9.1', '1.9.0')

• Interpolation now works in object literal keys (again). You can use this to dynamically name properties.
• Internal compiler variable names no longer start with underscores. This makes the generated JavaScript a bit prettier, and also fixes an issue with the completely broken and ungodly way that AngularJS “parses” function arguments.
• Fixed a few yield-related edge cases with yield return and yield throw.
• Minor bug fixes and various improvements to compiler error messages.

releaseHeader('2015-01-29', '1.9.0', '1.8.0')

• CoffeeScript now supports ES2015 generators. A generator is simply a function that yields.
• More robust parsing and improved error messages for strings and regexes — especially with respect to interpolation.
• Changed strategy for the generation of internal compiler variable names. Note that this means that @example function parameters are no longer available as naked example variables within the function body.
• Fixed REPL compatibility with latest versions of Node and Io.js.
• Various minor bug fixes.

releaseHeader('2014-08-26', '1.8.0', '1.7.1')

• The --join option of the CLI is now deprecated.
• Source maps now use .js.map as file extension, instead of just .map.
• The CLI now exits with the exit code 1 when it fails to write a file to disk.
• The compiler no longer crashes on unterminated, single-quoted strings.
• Fixed location data for string interpolations, which made source maps out of sync.
• The error marker in error messages is now correctly positioned if the code is indented with tabs.
• Fixed a slight formatting error in CoffeeScript’s source map-patched stack traces.
• The %% operator now coerces its right operand only once.
• It is now possible to require CoffeeScript files from Cakefiles without having to register the compiler first.
• The CoffeeScript REPL is now exported and can be required using require 'coffeescript/repl'.
• Fixes for the REPL in Node 0.11.

releaseHeader('2014-01-29', '1.7.1', '1.7.0')

• Fixed a typo that broke node module lookup when running a script directly with the coffee binary.

releaseHeader('2014-01-28', '1.7.0', '1.6.3')

• When requiring CoffeeScript files in Node you must now explicitly register the compiler. This can be done with require 'coffeescript/register' or CoffeeScript.register(). Also for configuration such as Mocha’s, use coffeescript/register.
• Improved error messages, source maps and stack traces. Source maps now use the updated //# syntax.
• Leading . now closes all open calls, allowing for simpler chaining syntax.
• Added **, // and %% operators and ... expansion in parameter lists and destructuring expressions.
• Multiline strings are now joined by a single space and ignore all indentation. A backslash at the end of a line can denote the amount of whitespace between lines, in both strings and heredocs. Backslashes correctly escape whitespace in block regexes.
• Closing brackets can now be indented and therefore no longer cause unexpected error.
• Several breaking compilation fixes. Non-callable literals (strings, numbers etc.) don’t compile in a call now and multiple postfix conditionals compile properly. Postfix conditionals and loops always bind object literals. Conditional assignment compiles properly in subexpressions. super is disallowed outside of methods and works correctly inside for loops.
• Formatting of compiled block comments has been improved.
• No more -p folders on Windows.
• The options object passed to CoffeeScript is no longer mutated.

releaseHeader('2013-06-02', '1.6.3', '1.6.2')

• The CoffeeScript REPL now remembers your history between sessions. Just like a proper REPL should.
• You can now use require in Node to load .coffee.md Literate CoffeeScript files. In the browser, text/literate-coffeescript script tags.
• The old coffee --lint command has been removed. It was useful while originally working on the compiler, but has been surpassed by JSHint. You may now use -l to pass literate files in over stdio.
• Bugfixes for Windows path separators, catch without naming the error, and executable-class-bodies-with- prototypal-property-attachment.

releaseHeader('2013-03-18', '1.6.2', '1.6.1')

• Source maps have been used to provide automatic line-mapping when running CoffeeScript directly via the coffee command, and for automatic line-mapping when running CoffeeScript directly in the browser. Also, to provide better error messages for semantic errors thrown by the compiler — with colors, even.
• Improved support for mixed literate/vanilla-style CoffeeScript projects, and generating source maps for both at the same time.
• Fixes for 1.6.x regressions with overriding inherited bound functions, and for Windows file path management.
• The coffee command can now correctly fork() both .coffee and .js files. (Requires Node.js 0.9+)

releaseHeader('2013-03-05', '1.6.1', '1.5.0')

• First release of source maps. Pass the --map flag to the compiler, and off you go. Direct all your thanks over to Jason Walton.
• Fixed a 1.5.0 regression with multiple implicit calls against an indented implicit object. Combinations of implicit function calls and implicit objects should generally be parsed better now — but it still isn’t good style to nest them too heavily.
• .coffee.md is now also supported as a Literate CoffeeScript file extension, for existing tooling. .litcoffee remains the canonical one.
• Several minor fixes surrounding member properties, bound methods and super in class declarations.

releaseHeader('2013-02-25', '1.5.0', '1.4.0')

• First release of Literate CoffeeScript.
• The CoffeeScript REPL is now based on the Node.js REPL, and should work better and more familiarly.
• Returning explicit values from constructors is now forbidden. If you want to return an arbitrary value, use a function, not a constructor.
• You can now loop over an array backwards, without having to manually deal with the indexes: for item in list by -1
• Source locations are now preserved in the CoffeeScript AST, although source maps are not yet being emitted.

releaseHeader('2012-10-23', '1.4.0', '1.3.3')

• The CoffeeScript compiler now strips Microsoft’s UTF-8 BOM if it exists, allowing you to compile BOM-borked source files.
• Fix Node/compiler deprecation warnings by removing registerExtension, and moving from path.exists to fs.exists.
• Small tweaks to splat compilation, backticks, slicing, and the error for duplicate keys in object literals.

releaseHeader('2012-05-15', '1.3.3', '1.3.1')

• Due to the new semantics of JavaScript’s strict mode, CoffeeScript no longer guarantees that constructor functions have names in all runtimes. See #2052 for discussion.
• Inside of a nested function inside of an instance method, it’s now possible to call super more reliably (walks recursively up).
• Named loop variables no longer have different scoping heuristics than other local variables. (Reverts #643)
• Fix for splats nested within the LHS of destructuring assignment.
• Corrections to our compile time strict mode forbidding of octal literals.

releaseHeader('2012-04-10', '1.3.1', '1.2.0')

• CoffeeScript now enforces all of JavaScript’s Strict Mode early syntax errors at compile time. This includes old-style octal literals, duplicate property names in object literals, duplicate parameters in a function definition, deleting naked variables, setting the value of eval or arguments, and more. See a full discussion at #1547.
• The REPL now has a handy new multi-line mode for entering large blocks of code. It’s useful when copy-and-pasting examples into the REPL. Enter multi-line mode with Ctrl-V. You may also now pipe input directly into the REPL.
• CoffeeScript now prints a Generated by CoffeeScript VERSION header at the top of each compiled file.
• Conditional assignment of previously undefined variables a or= b is now considered a syntax error.
• A tweak to the semantics of do, which can now be used to more easily simulate a namespace: do (x = 1, y = 2) -> …
• Loop indices are now mutable within a loop iteration, and immutable between them.
• Both endpoints of a slice are now allowed to be omitted for consistency, effectively creating a shallow copy of the list.
• Additional tweaks and improvements to coffee --watch under Node’s “new” file watching API. Watch will now beep by default if you introduce a syntax error into a watched script. We also now ignore hidden directories by default when watching recursively.

releaseHeader('2011-12-18', '1.2.0', '1.1.3')

• Multiple improvements to coffee --watch and --join. You may now use both together, as well as add and remove files and directories within a --watch’d folder.
• The throw statement can now be used as part of an expression.
• Block comments at the top of the file will now appear outside of the safety closure wrapper.
• Fixed a number of minor 1.1.3 regressions having to do with trailing operators and unfinished lines, and a more major 1.1.3 regression that caused bound functions within bound class functions to have the incorrect this.

releaseHeader('2011-11-08', '1.1.3', '1.1.2')

• Ahh, whitespace. CoffeeScript’s compiled JS now tries to space things out and keep it readable, as you can see in the examples on this page.
• You can now call super in class level methods in class bodies, and bound class methods now preserve their correct context.
• JavaScript has always supported octal numbers 010 is 8, and hexadecimal numbers 0xf is 15, but CoffeeScript now also supports binary numbers: 0b10 is 2.
• The CoffeeScript module has been nested under a subdirectory to make it easier to require individual components separately, without having to use npm. For example, after adding the CoffeeScript folder to your path: require('coffeescript/lexer')
• There’s a new “link” feature in Try CoffeeScript on this webpage. Use it to get a shareable permalink for your example script.
• The coffee --watch feature now only works on Node.js 0.6.0 and higher, but now also works properly on Windows.
• Lots of small bug fixes from @michaelficarra, @geraldalewis, @satyr, and @trevorburnham.

releaseHeader('2011-08-04', '1.1.2', '1.1.1')

Fixes for block comment formatting, ?= compilation, implicit calls against control structures, implicit invocation of a try/catch block, variadic arguments leaking from local scope, line numbers in syntax errors following heregexes, property access on parenthesized number literals, bound class methods and super with reserved names, a REPL overhaul, consecutive compiled semicolons, block comments in implicitly called objects, and a Chrome bug.

releaseHeader('2011-05-10', '1.1.1', '1.1.0')

Bugfix release for classes with external constructor functions, see issue #1182.

releaseHeader('2011-05-01', '1.1.0', '1.0.1')

When running via the coffee executable, process.argv and friends now report coffee instead of node. Better compatibility with Node.js 0.4.x module lookup changes. The output in the REPL is now colorized, like Node’s is. Giving your concatenated CoffeeScripts a name when using --join is now mandatory. Fix for lexing compound division /= as a regex accidentally. All text/coffeescript tags should now execute in the order they’re included. Fixed an issue with extended subclasses using external constructor functions. Fixed an edge-case infinite loop in addImplicitParentheses. Fixed exponential slowdown with long chains of function calls. Globals no longer leak into the CoffeeScript REPL. Splatted parameters are declared local to the function.

releaseHeader('2011-01-31', '1.0.1', '1.0.0')

Fixed a lexer bug with Unicode identifiers. Updated REPL for compatibility with Node.js 0.3.7. Fixed requiring relative paths in the REPL. Trailing return and return undefined are now optimized away. Stopped requiring the core Node.js util module for back-compatibility with Node.js 0.2.5. Fixed a case where a conditional return would cause fallthrough in a switch statement. Optimized empty objects in destructuring assignment.

releaseHeader('2010-12-24', '1.0.0', '0.9.6')

CoffeeScript loops no longer try to preserve block scope when functions are being generated within the loop body. Instead, you can use the do keyword to create a convenient closure wrapper. Added a --nodejs flag for passing through options directly to the node executable. Better behavior around the use of pure statements within expressions. Fixed inclusive slicing through -1, for all browsers, and splicing with arbitrary expressions as endpoints.

releaseHeader('2010-12-06', '0.9.6', '0.9.5')

The REPL now properly formats stacktraces, and stays alive through asynchronous exceptions. Using --watch now prints timestamps as files are compiled. Fixed some accidentally-leaking variables within plucked closure-loops. Constructors now maintain their declaration location within a class body. Dynamic object keys were removed. Nested classes are now supported. Fixes execution context for naked splatted functions. Bugfix for inversion of chained comparisons. Chained class instantiation now works properly with splats.

releaseHeader('2010-11-21', '0.9.5', '0.9.4')

0.9.5 should be considered the first release candidate for CoffeeScript 1.0. There have been a large number of internal changes since the previous release, many contributed from satyr’s Coco dialect of CoffeeScript. Heregexes (extended regexes) were added. Functions can now have default arguments. Class bodies are now executable code. Improved syntax errors for invalid CoffeeScript. undefined now works like null, and cannot be assigned a new value. There was a precedence change with respect to single-line comprehensions: result = i for i in list used to parse as result = (i for i in list) by default … it now parses as (result = i) for i in list.

releaseHeader('2010-09-21', '0.9.4', '0.9.3')

CoffeeScript now uses appropriately-named temporary variables, and recycles their references after use. Added require.extensions support for Node.js 0.3. Loading CoffeeScript in the browser now adds just a single CoffeeScript object to global scope. Fixes for implicit object and block comment edge cases.

releaseHeader('2010-09-16', '0.9.3', '0.9.2')

CoffeeScript switch statements now compile into JS switch statements — they previously compiled into if/else chains for JavaScript 1.3 compatibility. Soaking a function invocation is now supported. Users of the RubyMine editor should now be able to use --watch mode.

releaseHeader('2010-08-23', '0.9.2', '0.9.1')

Specifying the start and end of a range literal is now optional, eg. array[3..]. You can now say a not instanceof b. Fixed important bugs with nested significant and non-significant indentation (Issue #637). Added a --require flag that allows you to hook into the coffee command. Added a custom jsl.conf file for our preferred JavaScriptLint setup. Sped up Jison grammar compilation time by flattening rules for operations. Block comments can now be used with JavaScript-minifier-friendly syntax. Added JavaScript’s compound assignment bitwise operators. Bugfixes to implicit object literals with leading number and string keys, as the subject of implicit calls, and as part of compound assignment.

releaseHeader('2010-08-11', '0.9.1', '0.9.0')

Bugfix release for 0.9.1. Greatly improves the handling of mixed implicit objects, implicit function calls, and implicit indentation. String and regex interpolation is now strictly #{ … } (Ruby style). The compiler now takes a --require flag, which specifies scripts to run before compilation.

releaseHeader('2010-08-04', '0.9.0', '0.7.2')

The CoffeeScript 0.9 series is considered to be a release candidate for 1.0; let’s give her a shakedown cruise. 0.9.0 introduces a massive backwards-incompatible change: Assignment now uses =, and object literals use :, as in JavaScript. This allows us to have implicit object literals, and YAML-style object definitions. Half assignments are removed, in favor of +=, or=, and friends. Interpolation now uses a hash mark # instead of the dollar sign $ — because dollar signs may be part of a valid JS identifier. Downwards range comprehensions are now safe again, and are optimized to straight for loops when created with integer endpoints. A fast, unguarded form of object comprehension was added: for all key, value of object. Mentioning the super keyword with no arguments now forwards all arguments passed to the function, as in Ruby. If you extend class B from parent class A, if A has an extended method defined, it will be called, passing in B — this enables static inheritance, among other things. Cleaner output for functions bound with the fat arrow. @variables can now be used in parameter lists, with the parameter being automatically set as a property on the object — useful in constructors and setter functions. Constructor functions can now take splats.

releaseHeader('2010-07-12', '0.7.2', '0.7.1')

Quick bugfix (right after 0.7.1) for a problem that prevented coffee command-line options from being parsed in some circumstances.

releaseHeader('2010-07-11', '0.7.1', '0.7.0')

Block-style comments are now passed through and printed as JavaScript block comments – making them useful for licenses and copyright headers. Better support for running coffee scripts standalone via hashbangs. Improved syntax errors for tokens that are not in the grammar.

releaseHeader('2010-06-28', '0.7.0', '0.6.2')

Official CoffeeScript variable style is now camelCase, as in JavaScript. Reserved words are now allowed as object keys, and will be quoted for you. Range comprehensions now generate cleaner code, but you have to specify by -1 if you’d like to iterate downward. Reporting of syntax errors is greatly improved from the previous release. Running coffee with no arguments now launches the REPL, with Readline support. The <- bind operator has been removed from CoffeeScript. The loop keyword was added, which is equivalent to a while true loop. Comprehensions that contain closures will now close over their variables, like the semantics of a forEach. You can now use bound function in class definitions (bound to the instance). For consistency, a in b is now an array presence check, and a of b is an object-key check. Comments are no longer passed through to the generated JavaScript.

releaseHeader('2010-05-15', '0.6.2', '0.6.1')

The coffee command will now preserve directory structure when compiling a directory full of scripts. Fixed two omissions that were preventing the CoffeeScript compiler from running live within Internet Explorer. There’s now a syntax for block comments, similar in spirit to CoffeeScript’s heredocs. ECMA Harmony DRY-style pattern matching is now supported, where the name of the property is the same as the name of the value: {name, length}: func. Pattern matching is now allowed within comprehension variables. unless is now allowed in block form. until loops were added, as the inverse of while loops. switch statements are now allowed without switch object clauses. Compatible with Node.js v0.1.95.

releaseHeader('2010-04-12', '0.6.1', '0.6.0')

Upgraded CoffeeScript for compatibility with the new Node.js v0.1.90 series.

releaseHeader('2010-04-03', '0.6.0', '0.5.6')

Trailing commas are now allowed, a-la Python. Static properties may be assigned directly within class definitions, using @property notation.

releaseHeader('2010-03-23', '0.5.6', '0.5.5')

Interpolation can now be used within regular expressions and heredocs, as well as strings. Added the <- bind operator. Allowing assignment to half-expressions instead of special ||=-style operators. The arguments object is no longer automatically converted into an array. After requiring coffeescript, Node.js can now directly load .coffee files, thanks to registerExtension. Multiple splats can now be used in function calls, arrays, and pattern matching.

releaseHeader('2010-03-08', '0.5.5', '0.5.4')

String interpolation, contributed by Stan Angeloff. Since --run has been the default since 0.5.3, updating --stdio and --eval to run by default, pass --compile as well if you’d like to print the result.

releaseHeader('2010-03-03', '0.5.4', '0.5.3')

Bugfix that corrects the Node.js global constants __filename and __dirname. Tweaks for more flexible parsing of nested function literals and improperly-indented comments. Updates for the latest Node.js API.

releaseHeader('2010-02-27', '0.5.3', '0.5.2')

CoffeeScript now has a syntax for defining classes. Many of the core components (Nodes, Lexer, Rewriter, Scope, Optparse) are using them. Cakefiles can use optparse.coffee to define options for tasks. --run is now the default flag for the coffee command, use --compile to save JavaScripts. Bugfix for an ambiguity between RegExp literals and chained divisions.

releaseHeader('2010-02-25', '0.5.2', '0.5.1')

Added a compressed version of the compiler for inclusion in web pages as /v<%= majorVersion %>/browser-compiler/coffeescript.js. It’ll automatically run any script tags with type text/coffeescript for you. Added a --stdio option to the coffee command, for piped-in compiles.

releaseHeader('2010-02-24', '0.5.1', '0.5.0')

Improvements to null soaking with the existential operator, including soaks on indexed properties. Added conditions to while loops, so you can use them as filters with when, in the same manner as comprehensions.

releaseHeader('2010-02-21', '0.5.0', '0.3.2')

CoffeeScript 0.5.0 is a major release, While there are no language changes, the Ruby compiler has been removed in favor of a self-hosting compiler written in pure CoffeeScript.

releaseHeader('2010-02-08', '0.3.2', '0.3.0')

@property is now a shorthand for this.property. Switched the default JavaScript engine from Narwhal to Node.js. Pass the --narwhal flag if you’d like to continue using it.

releaseHeader('2010-01-26', '0.3.0', '0.2.6')

CoffeeScript 0.3 includes major syntax changes: The function symbol was changed to ->, and the bound function symbol is now =>. Parameter lists in function definitions must now be wrapped in parentheses. Added property soaking, with the ?. operator. Made parentheses optional, when invoking functions with arguments. Removed the obsolete block literal syntax.

releaseHeader('2010-01-17', '0.2.6', '0.2.5')

Added Python-style chained comparisons, the conditional existence operator ?=, and some examples from Beautiful Code. Bugfixes relating to statement-to-expression conversion, arguments-to-array conversion, and the TextMate syntax highlighter.

releaseHeader('2010-01-13', '0.2.5', '0.2.4')

The conditions in switch statements can now take multiple values at once — If any of them are true, the case will run. Added the long arrow ==>, which defines and immediately binds a function to this. While loops can now be used as expressions, in the same way that comprehensions can. Splats can be used within pattern matches to soak up the rest of an array.

releaseHeader('2010-01-12', '0.2.4', '0.2.3')

Added ECMAScript Harmony style destructuring assignment, for dealing with extracting values from nested arrays and objects. Added indentation-sensitive heredocs for nicely formatted strings or chunks of code.

releaseHeader('2010-01-11', '0.2.3', '0.2.2')

Axed the unsatisfactory ino keyword, replacing it with of for object comprehensions. They now look like: for prop, value of object.

releaseHeader('2010-01-10', '0.2.2', '0.2.1')

When performing a comprehension over an object, use ino, instead of in, which helps us generate smaller, more efficient code at compile time. Added :: as a shorthand for saying .prototype. The “splat” symbol has been changed from a prefix asterisk *, to a postfix ellipsis ... Added JavaScript’s in operator, empty return statements, and empty while loops. Constructor functions that start with capital letters now include a safety check to make sure that the new instance of the object is returned. The extends keyword now functions identically to goog.inherits in Google’s Closure Library.

releaseHeader('2010-01-05', '0.2.1', '0.2.0')

Arguments objects are now converted into real arrays when referenced.

releaseHeader('2010-01-05', '0.2.0', '0.1.6')

Major release. Significant whitespace. Better statement-to-expression conversion. Splats. Splice literals. Object comprehensions. Blocks. The existential operator. Many thanks to all the folks who posted issues, with special thanks to Liam O’Connor-Davis for whitespace and expression help.

releaseHeader('2009-12-27', '0.1.6', '0.1.5')

Bugfix for running coffee --interactive and --run from outside of the CoffeeScript directory. Bugfix for nested function/if-statements.

releaseHeader('2009-12-26', '0.1.5', '0.1.4')

Array slice literals and array comprehensions can now both take Ruby-style ranges to specify the start and end. JavaScript variable declaration is now pushed up to the top of the scope, making all assignment statements into expressions. You can use \ to escape newlines. The coffeescript command is now called coffee.

releaseHeader('2009-12-25', '0.1.4', '0.1.3')

The official CoffeeScript extension is now .coffee instead of .cs, which properly belongs to C#. Due to popular demand, you can now also use = to assign. Unlike JavaScript, = can also be used within object literals, interchangeably with :. Made a grammatical fix for chained function calls like func(1)(2)(3)(4). Inheritance and super no longer use __proto__, so they should be IE-compatible now.

releaseHeader('2009-12-25', '0.1.3', '0.1.2')

The coffee command now includes --interactive, which launches an interactive CoffeeScript session, and --run, which directly compiles and executes a script. Both options depend on a working installation of Narwhal. The aint keyword has been replaced by isnt, which goes together a little smoother with is. Quoted strings are now allowed as identifiers within object literals: eg. {"5+5": 10}. All assignment operators now use a colon: +:, -:, *:, etc.

releaseHeader('2009-12-24', '0.1.2', '0.1.1')

Fixed a bug with calling super() through more than one level of inheritance, with the re-addition of the extends keyword. Added experimental Narwhal support (as a Tusk package), contributed by Tom Robinson, including bin/cs as a CoffeeScript REPL and interpreter. New --no-wrap option to suppress the safety function wrapper.

releaseHeader('2009-12-24', '0.1.1', '0.1.0')

Added instanceof and typeof as operators.

releaseHeader('2009-12-24', '0.1.0', '8e9d637985d2dc9b44922076ad54ffef7fa8e9c2')

Initial CoffeeScript release.