Haxe 4.0.0-preview.4

Release Notes

Dear Community,

On behalf of the Haxe Foundation, we are proud to announce the official release of the Haxe 4.0.0-preview.4! It is available along with the changelog at https://haxe.org/download.

As a preview release, it should not be considered stable. However, we appreciate anyone testing this version which will help us with the real Haxe 4 release. Please report any issues here:

https://github.com/HaxeFoundation/haxe/issues.

Thank you very much for your help!

Improved compiler display services

Our focus for this release has been compiler display services. We implemented a new, JSON-RPC-based protocol which is utilized by the vshaxe Visual Studio Code Extension to provide a variety of new features:

• Support for auto-import
• Completion on override |
• Completion for structure field names
• Support for auto-generating structure declarations, functions, switches and more
• Context-aware, sorted toplevel completion
• Reference finding which explores modules that are not necessarily part of the compilation

Improved enum abstracts

Enum abstracts now get the treatment they deserve with a proper enum abstract syntax. Furthermore, values can now be omitted if the enum abstract is defined over Int or String:

enum abstract MyEnum(String) {
    var MyValue; // implicit = "MyValue"
}

enum abstract MyOtherEnum(Int) {
    var MyValue0; // implicit = 0
    var MyValue1; // implicit = 1
    var MyValue5 = 5;
    var MyValue6; // implicit = 6
}

Various syntactic improvements

• extern is now recognized as a field-level modifier and can be used instead of @:extern
• Metadata names can now use dots, e.g. @:haxe.json becomes a metadata entry named "haxe.json"
• Structure fields now consistently allow var ?x and final ?x, meaning the same as @:optional var x
• Type1 & Type2 is now a recognized syntax for intersection types. For the time being, it is only supported to merge structures (replacing the { >Type1, >Type2, } syntax) and for type parameter constraints (replacing T:(Type1, Type2) which has been removed from the language).

Lots of bugfixes

See the changelog for more!

Change Log

2018-06-12: 4.0.0-preview.4

New features:

• all : added JSON-RPC-based display protocol
• all : allow enum abstract syntax instead of @:enum abstract (#4282)
• all : allow extern on fields instead of @:extern
• all : support signature completion on incomplete structures (#5767)
• all : support auto-numbering and auto-stringification in enum abstracts (#7139)
• all : support Type1 & Type2 intersection syntax for type parameter constraints and structures (#7127)

General improvements and optimizations:

• all : reworked CLI usage/help output (#6862)
• all : implemented for loop unrolling (#3784)
• all : metadata can now use ., e.g. @:a.b. This is represented as a string (#3959)
• all : [breaking] disallow static extensions on implicit this (#6036)
• all : allow true and false expressions as type parameters (#6958)
• all : improved display support in many areas
• all : support override | completion
• all : make display/references and display/toplevel actually work sometimes
• all : allow var ?x and final ?x parsing in structures (#6947)
• all : improved overall robustness of the parser in display mode
• all : allow @:commutative on non-static abstract functions (#5599)
• js : added externs for js.Date (#6855)
• js : respect -D source-map flag to generate source maps in release builds
• js : enums are now generated as objects instead of arrays (#6350)
• eval : improved debugger, support conditional breakpoints

Removals:

• all : moved haxe.remoting to hx3compat
• js : moved js.XMLSocket to hx3compat
• neko : moved neko.net to hx3compat
• all : removed support for T:(A, B) constraint syntax

Bugfixes:

• all : fixed various issues with diagnostics
• all : fixed fields with default values for @:structInit classes (#5449)
• all : fixed Null<T> inconsistency in if/ternary expressions (#6955)
• all : fixed visibility check related to private constructors of sibling classes (#6957)
• all : fixed @:generic naming (#6968)
• all : fixed handling of type parameters in local functions (#6560)
• all : fixed resolution order between untyped and type parameters (#7113)
• all : fixed unification behavior in try/catch expressions (#7120)
• all : fixed field type being lost for Int expressions on Float fields (#7132)
• all : cleaned up inline handling (#7155)
• display : fixed completion in packages starting with underscore (#5417)
• php : fixed Reflect.callMethod with classes as first argument (#7106)
• eval : fixed internal exception surfacing in some context calls (#7007)
• eval : fixed Type.enumEq (#6710)
• flash : fixed silently swallowing exceptions in getters/setters when invoked with Reflect methods (#5460, #6871)

Standard Library:

• all : added resize to Array (#6869)
• all : [breaking] removed return this from some haxe.Http methods (#6980)