Changelog#

v0.18.0-rc3 - 2021-12-05#

• URL format in gleam.toml is now validated.
• The gleam deps list command has been added.
• Fixed a bug where changing requirements in gleam.toml would not cause deps to be re-resolved.
• Fixed a bug where locked deps would cause incompatible package requirements to be discarded.
• Development dependencies are now included in the applications listed in the generated OTP .app file.
• gleam.toml now includes an erlang.extra_applications key to specify extra OTP applications that need to be started.

v0.18.0-rc2 - 2021-11-26#

• Fixed a bug where OTP .app files would be generated with invalid syntax.
• Removed extra whitespace from newly generated projects.

v0.18.0-rc1 - 2021-11-25#

• Gleam can now compile Gleam projects.
• Gleam can now run tests with the gleam eunit command.
• Gleam can now run programs with the gleam run command.
• Gleam can now run an Erlang shell with the gleam shell command.
• Gleam can now resolve package versions for a Gleam project's dependency tree.
• Gleam can now download Hex packages.
• Gleam can now build dependency packages that are managed using Gleam or rebar3.
• Gleam is now the default build tool for new projects.
• The template names for gleam new have been changed.
• Fixed a bug where the error message for a record update with an unknown field would point to all the fields rather than the unknown one.
• Improved styling for inline code in generated documentation.
• New projects use v0.18 of the stdlib.

v0.17.0 - 2021-09-20#

• Functions now get special handling when being printed from JavaScript.

v0.17.0-rc2 - 2021-09-19#

• Errors thrown when no case clause or assignment pattern matches the subject value now include more debugging information when targetting JavaScript.
• New projects are generated using gleam_stdlib v0.17.1.

v0.17.0-rc1 - 2021-09-11#

• Redesigned the Gleam prelude to be a module of core classes when compiling to JavaScript. This improves the resulting generated code and makes debugging and interop easier.
• Projects without rebar3 can be generated using the gleam-lib template.
• JavaScript modules are imported using a camel case variable name to avoid name collisions with variables.
• Pipelines now use assignments in the generated code in order to preserve the order of any side effects.
• Fixed a bug where the compiler would crash rather than raise an error if a project contained a single module and attempted to import another.
• Special variable naming has been made more consistent in rendered Erlang and JavaScript.
• Conditional compilation can now be used to have different code within a module when compiling to a specific target.
• Fixed a bug where todo caused values not to be returned in JavaScript.
• Fixed a bug where multiple discarded function arguments generated invalid JavaScript.
• Fixed a bug where using JavaScript reserved words as function argument names caused generated invalid JavaScript.
• Fixed a bug where a case expression of just a catch-all pattern generated invalid JavaScript.
• Fixed a bug where the formatter would incorrectly render extra newlines below try expressions.
• Fixed a bug where tail recursive functions with arguments with the same name as JavaScript reserved words generated the wrong JavaScript.
• Fixed a bug where list equality would be incorrectly reported in JavaScript.
• Multiple subjects are now supported for case expressions in JavaScript.
• Fixed a bug where matching using a Bool or Nil literal as the subject for a case expression would produce invalid code when compiling to JavaScript.
• Unsupported feature error messages now include file path and line numbers for debugging.
• Bit string literals with no segment options or just the bit_string, utf8 or utf8_codepoint options can be constructed when compiling to JavaScript.
• The format of generated JavaScript has been improved.
• Fixed a bug where rendered JavaScript incorrectly incremented variables when reassigned in patterns.
• Added eval and arguments to JavaScript reserved words.
• Support for the deprecated tuple(x, y, ...) syntax has been removed in favor of the more concise (#(x, y, ...)). Use gleam format with the previous version of the compiler to auto-migrate.
• New OTP projects are generated using gleam_otp v0.1.6.
• Fixed a bug where the equality operators could return the incorrect value for records when compiling to JavaScript.
• Fixed a bug where todo could sometimes render invalid JavaScript when used as an expression in the generated code.
• An error is now emitted if the list spread syntax is used with no prepended elements [..xs].
• Fixed a bug where type errors inside piped expressions would be incorrectly be reported as being an incorrect usage of the pipe operator.
• Gleam modules with no public exports no longer render private members in Erlang.
• Fixed a bug where discard variables used in assert assignments would generate invalid Erlang code.
• Fixed a bug where some expressions as case subjects would generate invalid JavaScript code.
• Fixed a bug where some assignments as the final expression in a function would not return the correct value in JavaScript.
• Gleam packages imported in JavaScript now have the path prefix gleam-packages. This can be served from your web server or aliased in your package.json for NodeJS projects.
• Fixed a bug where the type checker would fail to generalise some type variables, causing module metadata writing to fail.
• Fixed a bug where tail call optimisation when compiling to JavaScript could result in incorrect code.
• Fixed a bug where variable names could be rendered incorrectly in closures.
• An error is now emitted if alternative patterns fail to define all the variables defined by the first pattern.
• New projects are generated using gleam_stdlib v0.17.0.
• New projects are generated using gleam_otp v0.2.0.

v0.16.1 - 2021-06-21#

• Values which are being imported more than once in an unqualified fashion now cause an error to be reported.
• Argument docs for custom type constructors are now rendered in the HTML documentation.
• Patterns can be used with try expresssions when compiling to JavaScript.
• Types and record constructors can now be aliased with an uppercase name when imported. Aliasing them with a lowercase name is no longer permitted.
• Fixed a bug where nested import paths could be rendered incorrectly in JavaScript.

v0.16.0 - 2021-06-17#

v0.16.0-rc4 - 2021-06-17#

• Fixed a bug where if a JavaScript global function was imported as an external function with the same name the generated code would diverge.

v0.16.0-rc3 - 2021-06-17#

• New projects are generated using gleam_stdlib v0.16.0.

v0.16.0-rc2 - 2021-06-08#

• Gleam now supports alternative patterns in case expressions for the JavaScript target.
• The gleam prelude module can now be imported when compiling to JavaScript.
• Fixed a bug where the prelude module could not be imported when using the old build compiler API.
• Fixed a bug where if a JavaScript global function was imported as an external function with the same name the generated code would diverge.
• Type error messages coming from pipe usage have been improved.

v0.16.0-rc1 - 2021-06-04#

• Gleam can now compile to JavaScript! Specify the --target javascript flag to gleam compile-package to use it today.
• A compile time error is now raised when multiple module level constants with the same name are defined.
• Fixed a bug where declaring a type constructor using reserved erlang keyword in its fields results in invalid erlang code being generated.
• Fixed a bug where calling a function with discarded labelled arguments incorrectly results in a compile error.
• Fixed a bug where assert statements return the wrong value.
• The gleam new command requires a root folder param, project name is optional and if not provided the project name will be inferred from the folder name.
• Generated Erlang record header files now contain Erlang type information.
• New OTP application projects depend on gleam_otp v0.1.5.
• The output of the formatter has been improved.

v0.15.1 - 2021-05-07#

• Fixed a bug where blocks that contained try expressions could be formatted incorrectly.

v0.15.0 - 2021-05-06#

Release Blog Post

v0.15.0-rc1 - 2021-05-05#

• Syntax highlighting of Gleam code in generated HTML documentation has been improved.
• Fixed a bug where markdown tables in rendered HTML documentation would have the incorrect background colour on every other row.
• Tuples now have a new, concise syntax variant: #(x, y, ...). Existing code can be auto-migrated to the new syntax by running gleam format.
• Fixed a bug where customt type constructors with Erlang keywords as names would generate invalid Erlang code.
• Gleam now supports \e string escapes.
• Values and types from the prelude can now be used in a qualified fashion by importing the gleam module.
• Empty lists can now be used in constants.
• Compiler performance has been improved when working with lists.
• Compiler performance has been improved when working with sequences of expressions.
• Assignments using let and assert are now expressions and no longer require a following expression in their containing block. They are now themselves expessions.
• Fixed a bug where tuple indexing could incorrectly claim a tuple is not of type tuple in some circumstances.
• Glean new command now checks if target folder exists, if so it returns an error.
• A compile time error is now raised if a module is defined with the name gleam.
• A compile time error is now raised if a module is defined with the a keyword in the name.
• New projects are generated using gleam_stdlib v0.15.0.
• New projects are generated at v0.1.0.

v0.14.4 - 2021-03-27#

• The Gleam compiler has been updated to compile with the new Rust v1.51.0.
• New project's gleam.toml has a comment that shows how to add a repository field.
• New projects no longer include a licence field in src/$APP.app.src by default.

v0.14.3 - 2021-03-20#

• Added an error hint when joining string using the + or +. operator.
• New projects are created with setup-erlang v1.1.2 and Erlang/OTP v23.2.
• Fixed a bug where the compiler would be unable to locate an imported module if a value from a nested module is used in a qualified fashion.

v0.14.2 - 2021-03-02#

• Project names can now contain numbers.

v0.14.1 - 2021-02-27#

• The error message for binary operators has been given more detail and hints.
• Fixed a bug where alternative patterns would incorrectly report unused variables.
• Fixed a bug where private types shadowed shadowed by values would incorrectly report unused variables.

v0.14.0 - 2021-02-18#

Release Blog Post

v0.14.0-rc2 - 2021-02-18#

• New projects are created with gleam_stdlib v0.14.0.

v0.14.0-rc1 - 2021-02-14#

• Gleam now generates Erlang typespecs.
• New projects no longer include a licence file by default.
• New projects can be created using the new escript template to generate a command line tool style program.
• A warning is emitted when a literal value is constructed but not used.
• Automatically generate a link to repository in docs if available.
• Code in HTML documentation is has highlighted syntax.
• Gleam now only supports \r, \n, \t, \", and \\ string escapes.
• A set of OCI container images are built automatically for each release.
• New compile time checks for invalid bit string literals and patterns have been added.
• The error messages for syntax errors in names have been improved.
• Fixed a bug where the repo URL would render incorrectly in HTML docs.
• Fixed a bug where piping a block can render invalid Erlang.
• New compile time warnings on unused types, functions and variables.
• The runtime error emitted by the todo keyword now carries additional information.
• The runtime error emitted by the assert keyword now carries additional information.
• Fixed a bug where bit string patterns would not correctly unify with the subject being pattern matches on.
• Documentation dark mode.
• Fixed a bug where some app.src properties were incorrectly named.
• --warnings-as-errors flag added to gleam build command.

v0.13.2 - 2021-01-14#

• ring dep upgraded to enable compilation on Apple M1 ARM processors.

v0.13.1 - 2021-01-13#

• Fix off-by-one error in message messages.

v0.13.0 - 2021-01-13#

Release Blog Post

• New Gleam projects use stdlib v0.13.0.

v0.13.0-rc2 - 2021-01-12#

• The version property in gleam.toml is now optional again.

v0.13.0-rc1 - 2021-01-09#

• Variable names now only have 1st letter capitalized when converted to erlang.
• Records defined in other modules can now be used in module constants.
• Documentation can link from functions, types & constants to their source code definitions on popular project hosting sites.
• Documentation hosted on HexDocs now has a version selector.
• Fixed a bug where the app project template rendered invalid code.
• Newly generated projects use stdlib v0.12.0.
• Named subexpressions in patterns now render correct Erlang.
• The anonymous function syntax now successfully parses with whitespace between fn and (.
• Fixed a bug where the formatter would incorrectly remove blocks around some binary operators.
• Constants can now be defined after they are used in functions
• The parser has been rewitten from scratch, dramatically improving error messages and compilation times.
• 1-1 and a-1 are now parsed as 1 - 1 and a - 1
• Further information has been added to the error messages when a function returns the wrong type.
• Further information has been added to the error messages when case clauses return different types.
• Fixed a bug where imported record constructors without labels used as an anonymous function generates incorrect Erlang.

v0.12.1 - 2020-11-15#

• The compiler can now discriminate between record access and module access for shadowed names
• The new command will no longer permit projects to be made with names that clash with Erlang standard library modules.
• The formatter now correctly treats lines of only whitespace as empty.
• The styling of tables in rendered HTML documentation has been improved.
• Rendered HTML documentation has regained its max-width styling.

v0.12.0 - 2020-10-31#

Release Blog Post

v0.12.0-rc4 - 2020-10-31#

• The rendered module documentation sidebar can now scroll independently to the page.
• Application projects now have the correct mod value in the generated .app.src.
• Records without fields can now be used in module constants.
• New application projects are now created used Gleam's type safe OTP pulled from Hex.

v0.12.0-rc3 - 2020-10-24#

v0.12.0-rc2 - 2020-10-24#

v0.12.0-rc1 - 2020-10-24#

• The utf8, utf16, and utf32 type specifiers are now only available in bit string construction, matching must be done with the codepoint versions.
• Functions may now be called before they are defined in a module. This enabled mutually recursive functions!
• Discarded variable names may now include numbers.
• Fixed a bug where discarded variables might generate incorrect Erlang.
• Added support tuple access in clause guards.
• New projects are created with version 1.0.2 of the setup-gleam GitHub action.
• New application projects are now created used Gleam's type safe OTP.
• Comments are now correctly handled on platforms that use \r\n line endings, such as Windows.

v0.11.2 - 2020-09-01#

• Fixed a bug where an imported constructor would emit an unused constructor warning when only used in pattern matching.

v0.11.1 - 2020-08-31#

• The formatter style has been improved to render function type arguments on a single line when possible, even if the return type will not fit on a single line.
• The format for printed types in error messages has been improved.
• Fixed a bug where the formatter would strip a constructor pattern spread when no fields are given.
• Fixed a bug where assigning the result of a block to a variable would generate incorrect Erlang.
• The formatter style has been improved for function calls that take a single block as an argument.
• Reserved words are no longer incorrectly permitted as project names.

v0.11.0 - 2020-08-28#

Release Blog Post

v0.11.0-rc3 - 2020-08-27#

• Bit strings now support non-literal strings as segment values.
• Fixed a bug where Erlang variables could be generated with incorrect names when defining an anonymous function.

v0.11.0-rc2 - 2020-08-24#

• The formatter style has been improved to render some single argument calls in a more compact style.

v0.11.0-rc1 - 2020-08-22#

• Field access now works before the custom type is defined.
• The error message returned by the compiler when the user tries to use unknown labelled arguments now handles multiple labels at once, and does not suggest labels they have already supplied.
• The formatter style has been improved to use a trailing comma on imports broken over multiple lines.
• The formatter style has been improved to wrap lists and bit strings over as few lines as possible if the elements are Ints, Floats, or Strings.
• The formatter style has been improved to preserve comments on labelled call arguments.
• The formatter style has been improved to preserve empty lines in assignments.
• The performance of the formatter has been improved.
• Records can be updated using the spread syntax. A warning is emitted if no fields are updated when using this syntax.
• Fixed a bug where type parameters can leak between different type definitions in a module.
• Markdown tables, footnotes, strikethroughs, and tasklists are now supported in documentation.
• Fixed a bug where generic types may be incorrectly unified.
• Ints and floats can now be written with underscores for clarity.
• The warning for a todo now includes the required type of the not-yet-implented expression.
• Holes can be used in type annotations to specify part of a type, leaving the rest for inference.
• The incorrect arity error now prints any missing labelled arguments.
• Fixed a bug where Erlang variables could be generated with incorrect names when directly calling an anonymous function.
• A warning is emitted when a type is imported or created but not used.
• Fixed a bug where Erlang variables names could clash when rebinding variables while similarly named variables ending in a number are in scope.
• Fixed a bug in the pretty printer which prevented the formatter from rendering sub-expressions in a single line when later code would not fit on the same line.
• The formatter style has been improved to render some single argument calls in a more compact style.
• Gleam now supports hex, octal, and binary literals.
• Rebar3 hex packages now include gleam.toml and gen.
• Newly generated projects use stdlib v0.11.0.

v0.10.1 - 2020-07-15#

• Fixed a bug where the compiler failed to return an error when type checking a tuple with the wrong arity in a pattern.
• The error message for a duplicate module member now shows the location of both definitions.
• Fix compiler bug where labelled arguments were being reordered incorrectly.

v0.10.0 - 2020-07-01#

Release Blog Post

• Newly generated projects use stdlib v0.10.1.
• Fixed a bug where discards inside bit string patterns generated invalid code.

v0.10.0-rc2 - 2020-06-30#

• Fixed a bug where variables names would be incorrectly generated when using alternative patterns.

v0.10.0-rc1 - 2020-06-29#

• Single letter module names are now permitted.
• Added support for bit string syntax.
• Support for the deprecated list prepend syntax has been removed.
• Added module level constants that are inlined at compile time.
• Public module level constants generate documentation.
• The formatter style has been improved to wrap and sort imports.
• The formatter now permits comments at the end of module function bodies.
• The formatter now skips files that match patterns defined in ignore files such as .gitignore and .ignore.
• Error message diagnostic code previews for type errors when using the the pipe operator have been made more accurate.
• Added support for list literals in clause guards.
• Fixed bug when reassigning a variable inside a case clause with alternative patterns.
• Todos can now take an optional label.

v0.9.1 - 2020-06-12#

• Fixed a bug where binary operators may lose required { }s when formatted.

v0.9.0 - 2020-06-01#

Release Blog Post

• Newly generated projects use stdlib v0.9.0.
• Additional information is printed to the console when generating HTML documentation from Gleam code.
• Fixed a bug where blocks on either side of a binary operator would be rendered without { }.

v0.9.0-rc1 - 2020-05-26#

• The formatter style has been improved.
• Numbers are now permitted in module names.
• Emitted Erlang code correctly adds parentheses around binary subexpressions to preserve precedence.
• Record names and fields are now escaped in .hrl files if they conflict with Erlang reserved words
• Annotations are now supported on let and assert expressions
• Formatter now accepts comments for the fields of a custom type's constructors
• Added opaque custom types, which have constructors that cannot be accessed from outside their own modules.
• Additional (arbitrary) markdown documentation pages can now be added and built with docs build.
• Fix code generation when calling functions returned through either record or tuple access
• Add lookup for Gleam source code in Mix's deps directory.
• Newly generated Gleam projects use the GitHub action gleam-lang/setup-erlang v1.1.0.
• Added support for custom type record literals in guards.
• Type variables are now correctly preserved within nested scopes.

v0.8.1 - 2020-05-19#

• The formatter now correctly handles unicode comments.

v0.8.0 - 2020-05-07#

Release Blog Post

• The docs build, docs publish, and docs remove commands can be used to compile HTML documentation locally, publish them to HexDocs, and remove them from HexDocs respectively.
• Type error reporting has been improved when using the pipe operator.
• Newly generated projects use stdlib v0.8.0.
• The compiler can now emit warnings. Currently there are warnings for using the old '|' syntax in lists and for todos.
• Will give a clearer error when a function given as an argument to another function doesn't match the type of the parameter.
• Fixed bug where imported type constructors had the incorrect arity.
• Fixed bug where a doing an unqualified import of a type constructor and giving it an alias would use the wrong name if it contained any values.
• Fixed a bug trying to access an imported constructor which contained values.
• Fixed a compiler crash that occured when trying to unify a tuple with something other than another tuple or a variable.
• Added support for tuple literals in guards.

v0.8.0-rc1 - 2020-04-28#

• Strings are now encoded as utf8 binaries in the generated Erlang.
• HTML documentation can now be generated from Gleam code by running gleam build --doc.
• Gleam code can be formatted using the gleam format command.
• The pipe operator |> will now attempt to insert the left hand side as the first argument to the right hand side if the right hand side is a call, removing the need for function capture boilerplate.
• A record.label syntax can now be used to access the fields of a custom type that have a single record variant.
• Anonymous functions can now have return type annotations.
• There is a todo keyword for type checking functions that have not yet been implemented.
• Tuples can be indexed into using the var.1 syntax.
• >, >=, <, and <= operators are now supported in case clause guards and can be used to check the ordering of integers.
• >., >=., <., and <=. operators are now supported in case clause guards and can be used to check the ordering of floats.
• The list prepend syntax is now [x, ..y]. The old [x | y] syntax is deprecated but will continue to work for now. The formatter will rewrite the old syntax to the new.
• Add new assert syntax for binding variables assert Ok(x) = result. In the future this will allow you to use a pattern that does not match all values.
• Added support for int and float literals in guards.
• Color codes are now only emitted in error output for interactive terminal sessions.
• Added a new .. syntax for discarding the remaining fields of a record.
• Using the same variable name multiple times in the same pattern will now raise an error.
• Discard can now be omitted in list tails in patterns, ie [x, ..] is the same as [x, .._]. The former is the prefered version and is emitted by the formatter.

v0.7.1 - 2020-03-03#

• Projects generated with gleam new use stdlib version 0.7.0.

v0.7.0 - 2020-03-01#

Release Blog Post

v0.7.0-rc1 - 2020-02-28#

• Type aliases can be defined to give concise names to frequently used types.
• Case expression clauses may have guards which can be used to require equality between specified variables in order for the clause to match.
• Case expression clauses may have alternative patterns, enabling one clause to match for multiple different possible patterns.
• Types may now be used before they are defined within their defining module.
• Fixed a bug where import paths would not be correctly resolved on Windows.
• Added job to create precompiled binary for 64-bit Windows when releasing.
• gleam new now creates a project that uses actions/checkout@v2.0.0 in its GitHub actions workflow.
• Labelled argument in functions may now be discarded by prefixing the name with an underscore, like unlabelled arguments.
• Sub-patterns can have names assigned to them within a pattern using the as keyword.
• The format of compiler error messages printed to the console has been improved by upgrading to a newer version of the codespan-reporting library.
• Type variables in the given and expected types will now be printed with the same name in type error messages if they are equivilent.
• A friendly error message is rendered when a case expression clause has the incorrect number of patterns for the subjects.
• A friendly error message is rendered when a .gleam file cannot be read.
• A friendly error message is rendered when the gleam new command fails to write the new project to the file system.
• A friendly error message is rendered when there is a cycle formed by module imports.
• Top level types are now printed in error messages for type parameter mismatches.
• The gen directory is now deleted before each compilation.
• gleam new now includes installation instructions for Hex packages in the generated README.
• gleam new now accepts a --description flag for including a description of the project in the README and .app.src file.
• Fixed a bug where variable names would be incorrectly generated in some situations when variable names are reused during and after a case expression.
• Performance of the Erlang code generator has been improved by removing some vector allocations.
• An error is emitted when multiple types with the same name are defined in or imported into a module.

v0.6.0 - 2019-12-25 🎄#

Release Blog Post

• Function capture syntax now supports labelled arguments.

v0.6.0-rc1 - 2019-12-23#

• Syntax for defining structs and enums have been unified into a singular custom type definition statement. Instances of these custom types are called records.
• Anonymous structs have been renamed tuples.
• Values and types can be given a new name when imported in the unqualified fashion using the import mod.{value as name} syntax.
• An error will be emitted if multiple values constructors are defined with the same name in a module.

v0.5.1 - 2019-12-23#

• Fixed a bug where invalid Erlang would be generated when using a local private function as a value.

v0.5.0 - 2019-12-16#

Release Blog Post

• Enum constructor arguments can now be labelled, allowing arguments to be given by name at the call site.
• An Erlang header file with a record definition is generated for each Gleam struct defined.
• gleam new creates a project at v1.0.0.
• Function calls are now properly escaped when the function name conflicts with an Erlang keyword.
• References to unqualified imported functions now generate correct Erlang code.
• Fixed a bug where variable rebinding would generate incorrect code in some case expressions.
• Fixed a bug where variable rebinding of function arguments would generate incorrect code.

v0.5.0-rc1 - 2019-11-26#

• Function arguments can be labelled, allowing arguments to be given by name at the call site.
• case expressions now accept multiple subjects, enabling pattern matching on multiple values simultaneously.
• Values and types can be imported from modules and references in an unqualified fashion.
• Named structs now have their name as the first element in the generated Erlang code. This enabled easier use from Erlang by defining records for them, as well as slightly clearer printf debugging.
• Anonymous structs have been introduced, serving as a quick and generic alternative to declared structs and as a format for interop with Erlang tuples.
• gleam new now accepts a --template flag to generate different styles of project. An OTP application template has been added alongside the existing OTP library template.
• gleam new now creates configuration for GitHub Actions, making Gleam projects ready for continuous integration out of the box.
• The syntax for defining enums, case expressions, and blocks has been changed to a syntax closer to that found in the C family of languages.
• The source code preview for functions that return a type incompatible with the functions annotations has been improved to be more precise.
• A helpful error message is rendered if an enum field contains a generic type that has not been declared.
• A bug has been fixed in which type mismatch errors originating from pattern matching would sometimes display the incorrect expected type.

v0.4.2 - 2019-10-22#

• Fixed a crash when an incorrect number of labelled struct arguments are given.
• Fixed a struct labelled argument being incorrect reported as already given.

v0.4.1 - 2019-09-29#

• Struct types with parameterised fields are now registered with the correct number of type parameters.

v0.4.0 - 2019-09-19#

Release Blog Post

• The struct data type has be introduced. Structs are pre-declared user defined data types with named fields and constant access time.
• The map and tuple data types has been removed, replaced by the struct data type.
• The generated code no longer contains export statements if no functions are exported from a module.
• Comparison operators have been specialised to operate only on Ints.
• The >. >=. <. and <=. comparison operators have been added for comparing Floats.
• It is now an error to export an enum which has a constructor that takes a private type as an argument.
• The error messages for defining multiple modules with the same name and for importing test modules into application code have been improved.
• Numbers are now permitted in type names and constructors.
• The Nil constructor will no longer erroneously be of type Int.

v0.3.0 - 2019-08-08#

Release Blog Post

• New project structure can be generated with the gleam new command.
• Functions can be annotated with their argument and return types. This may be used to restrict the function to a less general type than inferred by the compiler, or purely for documentation purposes.
• External function names and their target functions are now escaped in the generated code if they collide with Erlang keywords such as catch or or.
• Type error arising from the arguments of function calls have more accurate error diagnostics.
• Precompiled Gleam binaries are now available on the GitHub release page.
• Precompiled Docker images containing the Gleam binary are now available on DockerHub.
• The formatting of the Erlang code rendered by the compiler has been altered to improve legibility.
• A helpful error message is now rendered if the shorthand anonymous function syntax is used with too many underscores.
• A helpful error message is now rendered when attempting to import an unknown module.

v0.2.0 - 2019-06-25#

• Modules can now live within namespaces such as my_app/user/profile.
• The name of the variable created can be specified when importing a module using the import my_mod as name syntax.
• Function names and atoms are now escaped in the generated code if they collide with Erlang keywords such as catch or or.
• There is a shorthand syntax for prepending multiple elements to a list. [1, 2, 3 | my_list]

v0.1.2 - 2019-05-12#

• Types containing more than 26 type variables will no longer render with invalid type variable names.
• Types in error messages no longer have extra indentation that increases as the type gets larger.
• There is a new type Nil which is occupied by a single value (Nil). This type is used to represent the absence of a value and is commonly used with Result to model a value that is either present (Ok(value)) or absent (Error(Nil)).
• Zero arity enum constructors now generate the correct Erlang when used in modules other than the one they are defined in.

v0.1.1 - 2019-04-28#

• Error messages now display the path of the file containing the problem.
• Maps and modules with erroneous extra fields now have a custom error message.
• Rows with tails that are unbound type variables are now correctly unified in the type system. This fixes a bug in which maps and modules may sometimes fail to type check when there is no error.

v0.1.0 - 2019-04-15#

Release Blog Post

• Initial release!