glimpse/target

Types

Target

The build target that a package is being typechecked for. Definitions annotated with @target(erlang), @target(javascript), or a custom target name are only active for their target; definitions without a target attribute apply to all.

Erlang and Javascript are the targets the real compiler builds for, and Named(name) supports experimental backends with their own target names (e.g. @target(python)).

pub type Target {
  Erlang
  Javascript
  Named(name: String)
}

Constructors

```
Erlang
```
```
Javascript
```
```
Named(name: String)
```

Values

filter_for_target

</>

pub fn filter_for_target(
  module: glance.Module,
  target: Target,
) -> glance.Module

Remove definitions whose @target attribute does not match the active target. The real Gleam compiler performs this filtering before typechecking so that e.g. the @target(javascript) variant of a type or function is not seen when checking for erlang.

function_supported

</>

pub fn function_supported(
  target: Target,
  definition: glance.Definition(glance.Function),
) -> Bool

Whether a function definition is usable on the given target: pure Gleam functions and functions with a body run everywhere, while a body-less external function runs only on the targets its @external attributes name.

has_external_for_target

</>

pub fn has_external_for_target(
  target: Target,
  definition: glance.Definition(glance.Function),
) -> Bool

Whether a function’s @external attributes include one for the given target. A function with such an external uses the external implementation on this target and its Gleam body is not checked; a function whose externals are for other targets uses its body instead.