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Standard Library

std.build.engine

Unions

Union	Description
`BuildInput`	An input of a task.
`BuildOutput`	An output of a task.

Types

Type	Description
`BuildFlags`	The engine flags from the command line.
`BuildGraph<C>`	The tasks of a build and their dependencies.
`BuildInstance<F>`	One instance of a rule.
`BuildValue<T>`	Holds the value a task returns.
`BuildVariable`	An environment variable read by `env`.

Functions

Function	Description
`concat_infos(first: std.build.BuildTask[], second: std.build.BuildTask[]) -> std.build.BuildTask[]`	Concatenates two lists of tasks.
`each<T, R>(values: T[], register: fn(T) -> R[]) -> R[]`	Calls `register` for each value and concatenates the results.
`each_output<G, T, R>(instances: BuildInstance<G>[], pick: fn(G) -> T, register: fn(T, std.build.BuildTask) -> R[]) -> R[]`	Calls `register` for one output of each instance and concatenates the results.
`files_of<F>(instances: BuildInstance<F>[]) -> F[]`	Returns the files of each instance.
`infos_of<F>(instances: BuildInstance<F>[]) -> std.build.BuildTask[]`	Returns the task of each instance.
`main<C>(arguments: string[], setup: fn(string[]) -> Result<C, string>, graph: fn(C) -> BuildGraph<C>) -> i32`	Runs `setup`, builds the graph and runs the targets. Returns the exit code.
`rematch_files(files: std.io.Files) -> std.io.Files`	Matches the patterns of `files` again.

`BuildInput`

Case	Description
`file(std.io.File)`	A file.
`directory(std.io.Directory)`	A directory.
`files(std.io.Files)`	Files matched by glob patterns.
`variable(BuildVariable)`	An environment variable.
`context(string)`	The context, as text.
`code(string)`	The hash of the task's code.

`BuildOutput`

Case	Description
`file(std.io.File)`	A file.
`directory(std.io.Directory)`	A directory.
`files(std.io.Files)`	Files matched by glob patterns.
`later(fn() -> std.io.File)`	A file whose path is only known when the task runs.

`BuildFlags`

Field	Description
`verbose: bool`	Shows what `verbose` writes. Set by `--verbose`.
`force: bool`	Runs tasks even when they are up to date. Set by `--force`.
`trace: bool`	Writes the run to `.mew/trace.json`. Set by `--trace`.

`BuildGraph<C>`

Member	Description
`BuildGraph<C>::new(context: C) -> BuildGraph<C>`	Creates an empty graph for the context.
`action(name: string, run: fn(C) -> Result<(), string>, dependencies: ...std.build.BuildTask) -> std.build.BuildTask`	Adds a task that neither returns a value nor writes files.
`value(name: string, run: fn(C) -> Result<string, string>, dependencies: ...std.build.BuildTask) -> std.build.BuildTask`	Adds a task that returns a value as text.
`files(name: string, inputs: BuildInput[], outputs: BuildOutput[], run: fn(C) -> Result<(), string>, dependencies: ...std.build.BuildTask) -> std.build.BuildTask`	Adds a task that reads or writes files.
`group(name: string, dependencies: ...std.build.BuildTask) -> std.build.BuildTask`	Adds a task that only has dependencies.
`retry(info: std.build.BuildTask, times: i32)`	Retries the task up to `times` times when it fails.
`when(info: std.build.BuildTask, test: fn() -> bool)`	Runs the task only when `test` returns true.
`when_context(info: std.build.BuildTask, test: fn(C) -> bool)`	Runs the task only when `test` returns true for the context.
`teardown(run: fn(C, bool) -> Result<(), string>)`	Sets a function to run after the last task, passing whether the build succeeded.
`before(run: fn(C, std.build.BuildTask) -> Result<(), string>)`	Sets a function to run before each task.
`after(run: fn(C, std.build.BuildTask, bool) -> Result<(), string>)`	Sets a function to run after each task, passing whether it succeeded.
`execute(targets: string[], flags: BuildFlags) -> i32`	Runs the targets. Returns the exit code.

`BuildInstance<F>`

Field	Description
`info: std.build.BuildTask`	The task of the instance.
`files: fn() -> F`	The files the instance writes.

`BuildValue<T>`

Member	Description
`keep(result: Result<T, string>, text: fn(T) -> string) -> Result<string, string>`	Stores the value from `result` and returns it as text.
`get() -> T`	Returns the stored value.

`BuildVariable`

Field	Description
`name: string`	The name of the variable.
`value: Option<string>`	The value of the variable, or `none` if it is not set.

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