11.0.0-beta.1

🚀 Main New Feature

• Make uncurried mode opt-out: by default, every project is now in uncurried mode, unless "uncurried": false is specified in the project config. #6249

💅 Polish

• Removed duplicate Super_error implementation in syntax. #6246

🐛 Bug Fix

• Fix issue with inlining records in the presence of record coercion. #6256

11.0.0-alpha.6

💥 Breaking Change

• -bs-super-errors flag has been deprecated along with Super_errors. #6243
• @rescript/react >= 0.12.0-alpha.2 is now required because of the React.fragment's children type fix. #6238

🐛 Bug Fix

• Remove unnecessary require and import statements when using dynamic imports. #6232
• Fix option unboxing logic in the presence of untagged variants. #6233
• Fix printing of local module with type. #6212
• Adapting JSX4 to React.fragment's children type change ('children -> React.element) #6238

💅 Polish

• In uncurried mode, outcome printer swaps curried and uncurries function printing compared to legacy.
• Add location information to duplicate type definition error messages. #6199
• Replace normal module errors with Super_error module, and clean up Super_error. #6199
• Js.Json.t, Js.null and Js.nullable are now untagged variants representing their runtime values, instead of abstract types. #6218

11.0.0-alpha.5

🚀 Main New Feature

• Add support for Dynamic import. #5703
• GenType: Add moduleResolution option to customize extensions on emitted import statements. This helps to adjust output compatibility with TypeScript projects using ESM. #6182
  • node (default): Drop extensions.
  • node16: Use TS output's extensions. Make it ESM-compatible.
  • bundler: Use TS input's extensions. Make it ESM-compatible.
• Make untagged variants understand payloads defined as records. #6208

💥 Breaking Change

• Parse assert as a regular function. assert is no longer a unary expression. Example: before assert 1 == 2 is parsed as (assert 1) == 2, now it is parsed as assert(1 == 2). #6180

🐛 Bug Fix

• Make "rescript format" work with node 10 again and set minimum required node version to 10 in package.json. #6186
• Fix partial application for uncurried functions with labeled args #6198
• Add error messages for dangling doc comments/attributes and mutable in record type definition. #6206
• Fix issue with overlapping array and object in untagged variants #6219

11.0.0-alpha.4

🚀 Main New Feature

• Add surface syntax for partial application of uncurried functions: foo(1, ...). This corresponds to curried application in the old mode. #6166

🐛 Bug Fix

• Fix broken formatting in uncurried mode for functions with _ placeholder args. #6148
• Fix issue where spreading record types with optional labels would not have their labels preserved as optional. #6154
• Fix error location to be the type with the spreads when spreading record types with duplicate labels. #6157
• Disable warning on @inline attibute on uncurried functions. #6152
• Support doc comments on arguments of function types. #6161
• Fix issue with record type coercion and unboxed. #6158
• Fixed subtype checking for record types with @as attributes: The subtype relationship now takes into account the compatibility of @as attributes between corresponding fields, ensuring correctness in runtime representation.
  #6158
• Emit directive above header comment. #6172
• Add error message to private extension. #6175

💅 Polish

• Update list of reserved JS keywords. #6167
• Add error message to @@directive. #6174

11.0.0-alpha.3

🚀 Main New Feature

• Add support for extensible records (e.g. type t = {...t1, x:int, ...t2}) #5715

🐛 Bug Fix

• Fix formatting and parentheses placement in uncurried functions with constraints. #6143

11.0.0-alpha.2

🐛 Bug Fix

• Special case generation of uncurried functions with 1 argument of unit type so they don't take a parameter. #6131

🚀 Main New Features

• Add support for type coercion :> for records. #5721

11.0.0-alpha.1

🚀 Main New Features

• Introduce experimental uncurried mode. For experimentation only. PR #5796
• Customization of runtime representation of variants and introduction of untagged variants PR #6095, PR #6103

🚀 New Feature

• Add support for uncurried mode: a mode where everything is considered uncurried, whether with or without the .. This can be turned on with @@uncurried locally in a file. For project-level configuration in bsconfig.json, there's a boolean config "uncurried", which propagates to dependencies, to turn on uncurried mode.
  Since there's no syntax for partial application in this new mode, introduce @res.partial foo(x) to express partial application. This is temporary and will later have some surface syntax.
  Make uncurried functions a subtype of curried functions, and allow application for uncurried functions.
  The make function of components is generated as an uncurried function.
  Use best effort to determine the config when formatting a file.
  #5968 #6080 #6086 #6087
• Customization of runtime representation of variants. This is work in progress. E.g. some restrictions on the input. See comments of the form "TODO: put restriction on the variant definitions allowed, to make sure this never happens". #6095
• Introduce untagged variants #6103
• Add support for unary uncurried pipe in uncurried mode #5804
• Add support for partial application of uncurried functions: with uncurried application one can provide a
  subset of the arguments, and return a curried type with the remaining ones #5805
• Add support for uncurried externals #5815 #5819 #5830 #5894
• Parser/Printer: unify uncurried functions of arity 0, and of arity 1 taking unit. There's now only arity 1 in the source language. #5825
• Add support for default arguments in uncurried functions #5835
• Inline uncurried application when it is safe #5847
• Support optional named arguments without a final unit in uncurried functions #5907
• GenType: add the option to use the @genType annotation at the module level, meaning that all the items in the module should be exported. #6113
• GenType: add support for @genType annotations on module definitions. #6113
• Prebuilt binaries are now provided for all major platforms:
  • macOS x64
  • macOS ARM
  • Linux x64 (statically linked)
  • Linux ARM (statically linked)
  • Windows x64

💥 Breaking Change

• Remove support for the legacy Reason syntax. Existing Reason code can be converted to ReScript syntax using ReScript 9 as follows:
  • npm i -g rescript@9
  • rescript convert <reason files>
• Remove obsolete built-in project templates and the "rescript init" functionality. This is replaced by create-rescript-app which is maintained separately.
• Do not attempt to build ReScript from source on npm postinstall for platforms without prebuilt binaries anymore.
• Made pinned dependencies transitive: if a is a pinned dependency of b and b is a pinned dependency of c, then a is implicitly a pinned dependency of c. This change is only breaking if your build process assumes non-transitivity.
• Curried after uncurried is not fused anymore: (. x) => y => 3 is not equivalent to (. x, y) => 3 anymore. It's instead equivalent to (. x) => { y => 3 }.
  Also, (. int) => string => bool is not equivalen to (. int, string) => bool anymore.
  These are only breaking changes for unformatted code.
• Exponentiation operator ** is now right-associative. 2. ** 3. ** 2. now compile to Math.pow(2, Math.pow(3, 2)) and not anymore Math.pow(Math.pow(2, 3), 2). Parentheses can be used to change precedence.
• Remove unsafe j`$(a)$(b)` interpolation deprecated in compiler version 10 #6068
• Remove deprecated module Printexc
• @deriving(jsConverter) not supported anymore for variant types #6088
• New representation for variants, where the tag is a string instead of a number. #6088
• GenType: removed support for @genType.as for records and variants which has become unnecessary. Use the language's @as instead to channge the runtime representation without requiring any runtime conversion during FFI. #6099 #6101

🐛 Bug Fix

• Fix issue where uncurried was not supported with pipe #5803
• Fix printing of nested types in uncurried mode #5826
• Fix issue in printing uncurried callbacks #5828
• Fix formatting uncurried functions with attributes #5829
• Fix parsing/printing uncurried functions with type parameters #5849
• Fix compiler ppx issue when combining async and uncurried application #5856
• Fix issue where the internal representation of uncurried types would leak when a non-function is applied in a curried way #5892
• Fix some comments disappearing in array access expressions #5947
• Parser: fix location of variable when function definition {v => ...} is enclosed in braces #5949
• Fix issue with error messages for uncurried functions where expected and given type were swapped #5973
• Fix issue with integer overflow check #6028
• Make internal encoding of locations aware of unicode #6073
• Fix issue where foo(x,_) in uncurried mode would generate a curried function #6082
• Fix printing of uncurried application when the lhs is a function definition #6084
• Fix parsing uncurried type starting with path #6089
• Fix bigInt comparison #6097
• Fixed a bug where the async attribute was not preserved when using the @this decorator in ReScript functions. This fix allows proper handling of async functions with the @this decorator. Issue: #6100
• Fix issue with GenType and module aliases #6112

💅 Polish

• Syntax: process uncurried types explicitly in the parser/printer #5784 #5822
• Syntax: process uncurried function declarations explicitly in the parser/printer #5794
• PPX V4: allow uncurried make function and treat it like a curried one #5802 #5808 #5812
• Remove processing of objects expressions, which don't exist in .res syntax (Pexp_object) #5841
• Remove class type processing from compiler ppx #5842
• Remove method application via operator ##, which does not exist in .res syntax #5844
• Treat @meth annotation as making the type uncurried for backwards compatibitly with some examples #5845
• Process @set annotation for field update as generating an uncurried function #5846
• Treat uncurried application of primitives like curried application, which produces better output #5851
• New internal representation for uncurried functions using built-in type function$<fun_type, arity> this avoids having to declare all the possible arities ahead of time #5870
• PPX V3: allow uncurried make function and treat it like a curried one https://github.co...

10.1.4

🐛 Bug Fix

• Fix implementation of directives #6052
• Fix issue if the lib dir is included in the sources of bsconfig.json #6055
• Fix issue with string escape in pattern match #6062
• Fix issue with literal comparison of string constants #6065

🚀 New Feature

• Add support for toplevel await #6054

💅 Polish

• Better error message for extension point #6057
• Improve format check help #6056
• Deprecate unsafe j`$(a)$(b)` interpolation: use string templates `${a}${b}` instead #6067

10.1.3

🚀 New Feature

• Add experimental suppport for directives. An annotation such as @@directive("use client;") emits use client; verbatim before imports #5999
• genType: add Core standard library support for the following builtin types: Null.t, Nullable.t, Undefined.t, Dict.t<_>, Promise.t<_>, Date.t, BigInt.t, RegExp.t, Map.t<_, _>, WeakMap.t<_, _>, Set<_>, WeakSet<_> #6024

💥 Breaking Change

• genType: streamline the treatment of optionals as undefined #6024
  • Represent option<t> as undefined | t instead of null | undefined | t. This is more permissive when importing functions taking optional values (allows to use option types), but stricter when e.g. exporting ReScript functions taking arguments of option type. Fallback: use Js.undefined<_> instead.
  • Represent {x:option<string>} as {x:(undefined | string)} instead of {x?: string}. This is more in line with TS's behaviour. Fallback: use {x?:string}.

💅 Polish

• Add the gap property to jsxDOMStyle #5956

🐛 Bug Fix

• Fix issue where error messages related to non-existent props were displayed without location information rescript-lang/syntax#730
• Fix issue where uncurried functions were incorrectly converting the type of a prop given as a default value to curried rescript-lang/syntax#731
• Fix issue with nested async functions, where the inner function would be emitted without async #5984
• Fix issue with printing async functions with locally abstract types rescript-lang/syntax#732
• Fix issue with async context and locally abstract types #5985
• Fix support for recursive components in JSX V4 rescript-lang/syntax#733
• GenType: fix issue with V3 compatibility mode (see #5990) #5992
• Fix issue with overlapping labelled argument with default value rescript-lang/syntax#734
• Fix issue with using alias and default value together rescript-lang/syntax#734
• Fix issue in Js.Promise2 where then and catch were returning undefined #5996
• Fix issue in the compiler back-end where async functions passed to an @uncurry external would be inlined and transformed in a way that loses async #6011
• Fix location issue for the treatment of async functions where hovering on the body with a type error would show 'a => promise<'a> everywhere #6014
• Fix formatting of switch expressions that contain braced cases inside rescript-lang/syntax#735
• Fix formatting of props spread for multiline JSX expression rescript-lang/syntax#736
• Support @gentype.import as an alias to @genType.import in the compiler #6021
• In GenType, check annotations also in module types to decide whether to produce the .gen.tsx file #5903
• Fix issue with JSX V4 and newtype rescript-lang/syntax#737
• Fix issue with JSX V4 when components are nested rescript-lang/syntax#738
• Fix issue where generic compare on float values would be different from the compare for type float #6043
• Improve code generated for default arguments in JSX V4 rescript-lang/syntax#739
• Fix issue with JSX V4 props of the form ~p as module(...) rescript-lang/syntax#739

10.1.2

🐛 Bug Fix

• Fix an issue where error messages related to duplicate props were displayed without a loc and were unclear rescript-lang/syntax#728