changelog/v1.14.md
Fixed a bug where the formatter would remove @external attributes from
custom types.
(Surya Rose)
Fixed a bug where updating records with unlabelled fields would result in invalid code. (Surya Rose)
The output of echo when printing atoms has been updated to use
atom.create("...") instead of atom.create_from_string("...").
(Patrick Dewey)
Patterns aliasing a string prefix have been optimised to generate faster code on the Erlang target. (Giacomo Cavalieri)
Type inference for constants is now fault tolerant, meaning the compiler won't stop at the first error as it is typing constants. (Giacomo Cavalieri)
Analysis is now fault tolerant in the presence of errors in field definitions of custom type variants. (Adi Salimgereyev)
The compiler now emits a warning when a module contains no public definitions and prevents publishing packages with empty modules to Hex. (Vitor Souza)
The @external annotation is now supported for external types. It allows
users to point an external type definition to a specific Erlang or TypeScript
type. For example, the dict.Dict type from the standard library can now be
written as the following:
@external(erlang, "erlang", "map")
@external(javascript, "../dict.d.mts", "Dict")
pub type Dict(key, value)
When matching the wrong number of subjects, the compiler now pinpoints the error location instead of marking the entire branch.
case wibble {
0, _ -> 1
^^^^ Expected 1 pattern, got 2
0 | -> 1
^ I was expecting a pattern after this
}
(fruno)
Missing patterns in error messages and the "Add missing patterns" code action are no longer sorted lexicographically. Instead, they now consider the order in which variants were defined. As programmers often group "related" variants together, this should mean less reshuffling after inserting missing patterns! (fruno)
The performance of == and != has been improved for fieldless custom type
variants when compiling to JavaScript. This was done by generating comparison
code specific to the custom type rather than using the generic equality check
code.
(Nafi)
The lowercase bool pattern error is no longer a syntax error, but instead a part of the analysis step. This allows the entire module to be analyzed, rather than stopping at the syntax error. (mxtthias)
Exhaustiveness checks for ints and floats now correctly handle unreachable
cases in which the numbers contain underscores (i.e. 10 and 1_0).
Float exhaustiveness checks also now correctly identify unreachable cases
containing scientific notation or trailing zeros (i.e. 100 and 1e2).
(ptdewey)
The compiler now emits a warning when a doc comment is not attached to a definition due to a regular comment in between. For example, in the following code:
/// This documentation is not attached
// This is not a doc comment
/// This is actual documentation
pub fn wibble() {
todo
}
Will now produce the following warning:
warning: Detached doc comment
┌─ src/main.gleam:1:4
│
1 │ /// This documentation is not attached
│ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ This is not attached to a definition
This doc comment is followed by a regular comment so it is not attached to
any definition.
Hint: Move the comment above the doc comment
The interference-based pruning from 1.13 has been extended to int segments! Aside from the various performance improvements, this allows the compiler to mark more branches as unreachable.
case bits {
<<"a">> -> 0
<<97>> -> 1
// ^- This branch is unreachable because it's equal to "a".
<<0b1:1, _:1>> -> 2
<<0b11:2>> -> 3
// ^- This branch is unreachable because the branch before it already covers it.
_ -> 99
}
(fruno)
Comparison of record constructors with non-zero arity always produces False,
because under the hood during code generation they become anonymous functions:
pub type Wibble {
Wobble(String)
}
pub fn main() {
echo Wobble == Wobble // False
}
Previously compiler produced false-positive redundant comparison warning, which is now removed:
Record update syntax can now be used in constant definitions. For example:
pub const base_http_config = HttpConfig(
host: "0.0.0.0",
port: 8080,
use_tls: False,
log_level: Info,
)
pub const dev_http_config = HttpConfig(
..base_http_config,
port: 4000,
log_level: Debug,
)
pub const prod_http_config = HttpConfig(
..base_http_config,
port: 80,
use_tls: True,
log_level: Warn,
)
The help text displayed by gleam dev --help, gleam test --help, and
gleam run --help has been improved: now each one states which function it's
going to run.
(Giacomo Cavalieri)
The --invert and --package options of gleam deps tree are now mutually
exclusive; if both options are given the command will fail. Previously,
--invert would be silently ignored if given together with --package.
(Evan Silberman)
Updated to use the latest Elixir API, so a warning would not be shown when compiling Elixir file in a Gleam project. (Andrey Kozhev)
The build tool now has a new gleam deps outdated command that shows outdated
versions for dependencies. For example:
$ gleam deps outdated
Package Current Latest
------- ------- ------
wibble 1.4.0 1.4.1
wobble 1.0.1 2.3.0
The format used for gleam deps list and the notice of available major
version upgrades has been improved.
(Louis Pilfold)
gleam new now creates the project directory using the confirmed project
name when a suggested rename is accepted.
(Adi Salimgereyev)
The build tool now provides better error message when trying to build Git dependencies without Git installed. Previously, it would show this error:
error: Shell command failure
There was a problem when running the shell command `git`.
The error from the shell command library was:
Could not find the stdio stream
Now it will show:
error: Program not found
The program `git` was not found. Is it installed?
Documentation for installing Git can be viewed here:
https://git-scm.com/book/en/v2/Getting-Started-Installing-Git
The language server can now offer a code action to merge case clauses with the same body. For example:
case user {
Admin(name:, ..) -> todo
//^^^^^^^^^^^^^^^^^^^^^^^^
Guest(name:, ..) -> todo
//^^^^^^^^^^^^^^^^ Selecting these two branches you can
// trigger the "Merge case branches" code action
_ -> todo
}
Triggering the code action would result in the following code:
case user {
Admin(name:, ..) | Guest(name:, ..) -> todo
_ -> todo
}
The "generate function" code action can now pick better names for arguments that use the record access syntax. For example:
pub type User {
User(id: Int, name: String)
}
pub fn go(user: User) {
authenticate(user.id, user.name)
todo
}
Having the language server generate the missing authenticate function will
produce the following code:
pub fn authenticate(id: Int, name: String) {
todo
}
The "inline variable" code action can now trigger when used over the let
keyword of a variable to inline.
(Giacomo Cavalieri)
The "add omitted labels" code action can now be used in function calls where some of the labels have been provided already. (Giacomo Cavalieri)
The "generate function" code action can now trigger when used over constant values as well. (Giacomo Cavalieri)
Grouping of related diagnostics should now work across more editors. Warnings will display together with their hints and you no longer have "go to next diagnostic" twice in a row. Zedlings rejoice! (fruno)
The "pattern match on variable" code action can now pick better names when used on tuples. (Giacomo Cavalieri)
When renaming, if the new name is invalid, the language server will produce an error message instead of silently doing nothing. (Giacomo Cavalieri)
When providing autocomplete suggestions, the language server will now prioritise values which match the expected type of the value being completed. (Surya Rose)
The language server now offers code action to add type annotations to all functions and constants. For example,
pub const answer = 42
pub fn add(x, y) {
x + y
}
pub fn add_one(thing) {
// ^ Triggering "Annotate all top level definitions" code action here
let result = add(thing, 1)
result
}
Triggering the "Annotate all top level definitions" code action over
the name of function add_one would result in following code:
pub const answer: Int = 42
pub fn add(x: Int, y: Int) -> Int {
x + y
}
pub fn add_one(thing: Int) -> Int {
let result = add(thing, 1)
result
}
Qualify and unqualify code actions can now trigger when used over constant values as well. (Vladislav Shakitskiy)
Fixed two bugs that made gleam not update the manifest correctly, causing it to hit hex for version resolution on every operation and quickly reach request limits in large projects. (fruno)
Fixed a bug where renaming a variable from an alternative pattern would not rename all its occurrences. (Giacomo Cavalieri)
The compiler now reports an error for literal floats that are outside the floating point representable range on both targets. Previously it would only do that when compiling on the Erlang target. (Giacomo Cavalieri)
Fixed a typo in the error message emitted when trying to run a module that does not have a main function. (Louis Pilfold)
Fixed a bug where the "Generate function" code action would be incorrectly offered when calling a function unsupported by the current target, leading to invalid code if the code action was accepted. (Surya Rose)
Fixed a bug where the formatter would not remove the right number of double negations from literal integers. (Giacomo Cavalieri)
Fixed a typo for the "Invalid number of patterns" error. (Giacomo Cavalieri)
Fixed a stack overflow when type checking some case expressions with thousands of branches. (fruno)
The "add omitted label" code action no longer adds labels to arguments
being piped in or the callbacks of use.
(fruno)
Fixed a bug that caused the compiler to incorrectly optimise away runtime
size checks in bit array patterns on the javascript target if they used
calculations in the size of a segment (_:size(wibble - wobble)).
(fruno)
Add a missing BitArray constructor return type in the prelude's TypeScript definitions. (Richard Viney)
Fixed a bug where the BEAM would be shut down abruptly once the program had successfully finished running. (Louis Pilfold)
Fixed a bug where the "pattern match on variable" code action would generate invalid code when applied on a list's tail. (Giacomo Cavalieri)
Fixed a bug where the "pattern match on variable" code action would generate invalid patterns by repeating a variable name already used in the same pattern. (Giacomo Cavalieri)
Fixed a bug where the "generate function" code action would pop up for variants. (Giacomo Cavalieri)
Fixed a bug where useless comparison warnings for floats compared literal
strings, claiming for example that 1.0 == 1. was always false.
(fruno)
Fixed a bug where pattern variables in case clause guards would incorrectly shadow outer scope variables in other branches when compiling to JavaScript. (Elias Haider)
Fix invalid TypeScript definition being generated for variant constructors with long names that take no arguments. (Richard Viney)
Fixed a bug where the formatter would remove the @deprecated attribute from
constants.
(Surya Rose)
Fixed a bug where invalid code would be generated on the JavaScript target in cases where an underscore followed the decimal point in a float literal. (Patrick Dewey)
Typos in the error message shown when trying to install a non-existent package have been fixed. (Ioan Clarke)
Fixed a bug where the compiler would generate invalid Erlang and TypeScript code for unused opaque types referencing private types. (Surya Rose)
Fixed a bug where the type checker would allow invalid programs when a large group of functions were all mutually recursive. (Surya Rose)
The compiler now provides a clearer error message when a function's return
type is mistakenly declared using : instead of ->.
(Gurvir Singh)
Fixed a bug where the data generated for searching documentation was in the wrong format, preventing it from being used by Hexdocs search. (Surya Rose)
Fixed a bug where the "collapse nested case" code action would produce invalid code on a list tail pattern. (Matias Carlander)
Fixed two bugs that made gleam not update the manifest correctly, causing it to hit hex for version resolution on every operation and quickly reach request limits in large projects. (fruno)