Safe Haskell | None |
---|---|
Language | Haskell2010 |
Quasiquoters for external commands
- sh_ :: QuasiQuoter
- sh :: QuasiQuoter
- shell :: FilePath -> QuasiQuoter
- interpreter :: FilePath -> QuasiQuoter
- quoter :: (String -> Q Exp) -> QuasiQuoter
- callCommand :: FilePath -> [String] -> String -> Q Exp
- module System.Command.QQ.Embed
- module System.Command.QQ.Eval
Quasiquoters
Default shell
sh_ :: QuasiQuoter Source
Simple quasiquoter for the default shell
sh
analog that always constructs an action of type
IO ()
and so can always be used without type annotations
>>>
[sh_|echo "hello, world!"|]
hello, world!
sh :: QuasiQuoter Source
Quasiquoter for the default shell
Constructs polymorphic action of type Eval a => a
from passed string.
Uses SHELL
environment variable as path to shell executable
or /bin/sh
if it is unset.
>>>
[sh|echo "hello, world!"|] :: IO ExitCode
ExitSuccess>>>
[sh|echo "hello, world!"|] :: IO Text
"hello, world!\n"
Haskell values can be embedded with Ruby-like syntax:
>>>
let apples = 7
>>>
[sh|echo "#{apples} apples!"|] :: IO Text
"7 apples!\n"
Constructors
shell :: FilePath -> QuasiQuoter Source
Shell's quasiquoter constructor
"Shell" here means executable that has the following API:
<SHELL> -c <COMMAND>
e.g. sh
, bash
, zsh
, ksh
, tcsh
, python
, etc
interpreter :: FilePath -> QuasiQuoter Source
Interpreter's quasiquoter constructor
"Interpreter" here means executable that has the following API:
<INTERPRETER> -e <COMMAND>
e.g. perl
, ruby
, ghc
, etc
Customizations
quoter :: (String -> Q Exp) -> QuasiQuoter Source
Construct quasiquoter from function taking the string and producing Haskell expression.
Other kinds of quasiquoters (patterns, types or declarations quasiquoters) will fail in compile time
:: FilePath | Command path |
-> [String] | Arguments that go to command before quasiquoter contents |
-> String | Quasiquoter contents |
-> Q Exp |
Construct Haskell expression for external command call
module System.Command.QQ.Embed
module System.Command.QQ.Eval