| Safe Haskell | None |
|---|---|
| Language | Haskell2010 |
Development.Shake.Config
Description
A module for parsing and using config files in a Shake build system. Config files consist of variable bindings, for example:
# This is my Config file
HEADERS_DIR = /path/to/dir
CFLAGS = -g -I${HEADERS_DIR}
CFLAGS = $CFLAGS -O2
include extra/file.cfgThis defines the variable HEADERS_DIR (equal to /path/to/dir), and
CFLAGS (equal to -g -I/path/to/dir -O2), and also includes the configuration
statements in the file extra/file.cfg. The full lexical syntax for configuration
files is defined here: https://ninja-build.org/manual.html#_lexical_syntax.
The use of Ninja file syntax is due to convenience and the desire to reuse an
externally-defined specification (but the choice of configuration language is mostly arbitrary).
To use the configuration file either use readConfigFile to parse the configuration file
and use the values directly, or usingConfigFile and getConfig to track the configuration
values, so they become build dependencies.
- readConfigFile :: FilePath -> IO (HashMap String String)
- readConfigFileWithEnv :: [(String, String)] -> FilePath -> IO (HashMap String String)
- usingConfigFile :: FilePath -> Rules ()
- usingConfig :: HashMap String String -> Rules ()
- getConfig :: String -> Action (Maybe String)
- getConfigKeys :: Action [String]
Documentation
readConfigFile :: FilePath -> IO (HashMap String String) Source #
Read a config file, returning a list of the variables and their bindings. Config files use the Ninja lexical syntax: https://ninja-build.org/manual.html#_lexical_syntax
readConfigFileWithEnv :: [(String, String)] -> FilePath -> IO (HashMap String String) Source #
Read a config file with an initial environment, returning a list of the variables and their bindings. Config files use the Ninja lexical syntax: https://ninja-build.org/manual.html#_lexical_syntax
usingConfig :: HashMap String String -> Rules () Source #
Specify the values to use with getConfig, generally prefer
usingConfigFile unless you also need access to the values
of variables outside Action.
getConfig :: String -> Action (Maybe String) Source #
Obtain the value of a configuration variable, returns Nothing to indicate the variable
has no binding. Any build system using getConfig must call either usingConfigFile
or usingConfig. The getConfig function will introduce a dependency on the configuration
variable (but not the whole configuration file), and if the configuration variable changes, the rule will be rerun.
As an example:
usingConfigFile"myconfiguration.cfg" "*.o"%>\out -> do cflags <-getConfig"CFLAGS"cmd"gcc" [out-<.>"c"] (fromMaybe "" cflags)
getConfigKeys :: Action [String] Source #
Obtain the configuration keys.
Any build system using getConfigKeys must call either usingConfigFile or usingConfig.
The getConfigKeys function will introduce a dependency on the configuration keys
(but not the whole configuration file), and if the configuration keys change, the rule will be rerun.
Usually use as part of an action.
As an example:
usingConfigFile"myconfiguration.cfg"action$ need =<< getConfigKeys