shake-0.15.10: Build system library, like Make, but more accurate dependencies.

Safe Haskell | None
Language | Haskell2010

Development.Shake.Forward

Description

A module for producing forward-defined build systems, in contrast to standard backwards-defined build systems such as shake. Based around ideas from fabricate. As an example:

    import Development.Shake
    import Development.Shake.Forward
    import Development.Shake.FilePath

    main = shakeArgsForward shakeOptions $ do
        contents <- readFileLines "result.txt"
        cache $ cmd "tar -cf result.tar" contents

Compared to backward-defined build systems (such as normal Shake), forward-defined build systems tend to be simpler for simple systems (less boilerplate, more direct style), but more complex for larger build systems (requires explicit parallelism, explicit sharing of build products, no automatic command line targets). As a general approach for writing forward-defined systems:

- Figure out the sequence of system commands that will build your project.
- Write a simple `Action` that builds your project.
- Insert `cache` in front of most system commands.
- Replace most loops with `forP`, where they can be executed in parallel.
- Where Haskell performs real computation, if zero-build performance is insufficient, use `cacheAction`.

All forward-defined systems use `AutoDeps`, which requires `fsatrace` to be on the `$PATH`. You can obtain `fsatrace` from https://github.com/jacereda/fsatrace.

Synopsis

- shakeForward :: ShakeOptions -> Action () -> IO ()
- shakeArgsForward :: ShakeOptions -> Action () -> IO ()
- forwardOptions :: ShakeOptions -> ShakeOptions
- forwardRule :: Action () -> Rules ()
- cache :: (forall r. CmdArguments r => r) -> Action ()
- cacheAction :: String -> Action () -> Action ()

# Documentation

shakeForward :: ShakeOptions -> Action () -> IO () #

Run a forward-defined build system.

shakeArgsForward :: ShakeOptions -> Action () -> IO () #

Run a forward-defined build system, interpretting command-line arguments.

forwardOptions :: ShakeOptions -> ShakeOptions #

Given a `ShakeOptions`, set the options necessary to execute in forward mode.

forwardRule :: Action () -> Rules () #

Given an `Action`, turn it into a `Rules` structure which runs in forward mode.

cache :: (forall r. CmdArguments r => r) -> Action () #

Apply caching to an external command.

cacheAction :: String -> Action () -> Action () #

Cache an action. The name of the action must be unique for all different actions.