diff --git a/.gitignore b/.gitignore --- a/.gitignore +++ b/.gitignore @@ -1,5 +1,3 @@ # stack build artifacts .stack-work/ - -# Using hpack, we don't store cabal files -*.cabal +stack.yaml.lock diff --git a/LICENSE b/LICENSE --- a/LICENSE +++ b/LICENSE @@ -1,4 +1,4 @@ -Copyright (c) 2013-2018, Dino Morelli +Copyright (c) 2013, Dino Morelli Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided diff --git a/README.md b/README.md --- a/README.md +++ b/README.md @@ -3,19 +3,19 @@ ## Synopsis -Haskell shell script template (Haskell) +Haskell shell script templates (Haskell) ## Description -A template for writing shell scripts in Haskell. Contains some -useful functions and examples of things commonly done in bash. +Templates for writing shell scripts in Haskell. Includes some useful functions +and examples of things commonly done in bash. And an example of using +optparse-applicative in a shell script. ## Getting source - Download the cabalized source package [from Hackage](http://hackage.haskell.org/package/hscrtmpl) -- Get the source with darcs: `$ git clone https://github.com/dino-/hscrtmpl.git` - Get the source with stack: `$ stack unpack hscrtmpl` - If you're just looking, [browse the source](https://github.com/dino-/hscrtmpl) diff --git a/Setup.hs b/Setup.hs deleted file mode 100644 --- a/Setup.hs +++ /dev/null @@ -1,2 +0,0 @@ -import Distribution.Simple -main = defaultMain diff --git a/args-example.hs b/args-example.hs new file mode 100644 --- /dev/null +++ b/args-example.hs @@ -0,0 +1,101 @@ +#! /usr/bin/env stack +-- stack runghc --package ansi-wl-pprint --package heredoc --package optparse-applicative +{-# LANGUAGE QuasiQuotes #-} + +-- If you need a specific resolver, do this: +-- stack --resolver lts-16.11 runghc --package ... + +{- + This is a 'skeleton file' for writing shell scripts with Haskell that have + sophisticated arg parsing with optparse-applicative. + + The idea here is to take a copy of this script and hack it to do what you + need quickly. Throw the rest out. + + For more examples of doing common shell tasks, see the hscrtmpl.hs script + also in this project. + + + Dino Morelli + https://github.com/dino-/hscrtmpl + version: 2.0 2023-06-27 +-} + +import Options.Applicative +import System.Environment ( getProgName ) +import Text.Heredoc ( here ) +import Text.PrettyPrint.ANSI.Leijen ( string ) +import Text.Printf ( printf ) + + +main :: IO () +main = do + opts <- parseOpts + print opts + + +data Verbosity = Normal | Verbose + deriving Show -- For debugging, possibly not needed + +data Options = Options + { optSwitch :: Bool + , optMaybeString :: Maybe String + , optFlag :: Verbosity + , optString :: String + , optArgument :: String + , optArguments :: [String] + } + deriving Show -- For debugging, possibly not needed + + +parseOpts :: IO Options +parseOpts = do + pn <- getProgName + execParser $ info (parser <**> helper) + ( header (printf "%s - Argument parsing demo script" pn) + <> footer' + ) + + +-- For more help on building parsers: https://github.com/pcapriotti/optparse-applicative +parser :: Parser Options +parser = Options + <$> ( switch + ( long "switch" <> short 's' + <> help "A switch option" + ) + ) + <*> ( optional $ strOption + ( long "maybe-string" <> short 'm' <> metavar "STRING" + <> help "An optional string option" + ) + ) + <*> ( flag Normal Verbose + ( long "verbose" <> short 'v' + <> help "A flag option" + ) + ) + <*> ( strOption + ( long "string" <> short 'S' <> metavar "STRING" + <> help "A required string option" + ) + ) + <*> ( argument str + ( metavar "DIR" + <> help "A required single argument" + ) + ) + <*> some ( argument str + ( metavar "FILES..." + <> help "Multiple arguments, one or more required" + ) + ) + + +footer' :: InfoMod a +footer' = footerDoc . Just $ string content + where content = [here|OVERVIEW + +Put more info here about what this script is for and how it works + +v2.0 2023-06-27 Dino Morelli |] diff --git a/changelog.md b/changelog.md --- a/changelog.md +++ b/changelog.md @@ -1,3 +1,30 @@ +2.0 (2023-06-28) + + * Wrote a new args-example script + * Added a note about specifying the Stackage resolver + * Switched to modern cabal file instead of hpack + * Moved Stackage resolver up to 16.11 (ghc 8.8.3) + * Removed Setup.hs + * Added example of custom error message with lookupEnv + * Removed instructions for darcs + * Removed later copyright date + * Reorganized the functions in args-example.hs + * Updated cabal file and README to reflect multiple scripts + + +1.8 (2021-09-05) + + * Moved copyright up to 2021 + * Added stack.yaml.lock to .gitignore + * Replace forSystem function + + +1.7 (2019-08-22) + + * Added sequence expression example + * Replaced a case statement with an if + + 1.6 (2018-10-03) * Moved copyright date up to 2018 diff --git a/hscrtmpl.cabal b/hscrtmpl.cabal --- a/hscrtmpl.cabal +++ b/hscrtmpl.cabal @@ -1,43 +1,63 @@ --- This file has been generated from package.yaml by hpack version 0.28.2. --- --- see: https://github.com/sol/hpack --- --- hash: 94422872b0ab311808f7510b45c6c5bb31ee6db2edcd9e2d75de1aa77c28bb29 +cabal-version: 2.2 name: hscrtmpl -version: 1.6 -synopsis: Haskell shell script template -description: A template for writing shell scripts in Haskell. Contains some useful functions and examples of things commonly done in bash. +version: 2.0 +synopsis: Haskell shell script templates +description: Templates for writing shell scripts in Haskell. Includes some useful functions and examples of things commonly done in bash. And an example of using optparse-applicative in a shell script. category: Application, Console, Scripting homepage: https://github.com/dino-/hscrtmpl#readme bug-reports: https://github.com/dino-/hscrtmpl/issues author: Dino Morelli -maintainer: dino@ui3.info -copyright: 2018 Dino Morelli +maintainer: Dino Morelli +copyright: 2013 Dino Morelli license: ISC license-file: LICENSE build-type: Simple -cabal-version: >= 1.10 extra-source-files: - .gitignore - changelog.md - package.yaml - README.md - stack.yaml + changelog.md + .gitignore + README.md + stack.yaml source-repository head type: git location: https://github.com/dino-/hscrtmpl +-- Hey! These source files are *scripts*, you don't have to build them unless +-- you want to have a binary! + +common lang + default-language: Haskell2010 + other-modules: + Paths_hscrtmpl + autogen-modules: + Paths_hscrtmpl + build-depends: + process + ghc-options: + -fwarn-tabs + -Wall + -Wcompat + -Wincomplete-record-updates + -Wincomplete-uni-patterns + -Wredundant-constraints + executable hscrtmpl + import: lang main-is: hscrtmpl.hs - other-modules: - Paths_hscrtmpl - ghc-options: -fwarn-tabs -Wall -Wcompat -Wincomplete-record-updates -Wincomplete-uni-patterns -Wredundant-constraints build-depends: base >=3 && <5 , directory , filepath - , process + -- , regex-compat , time - default-language: Haskell2010 + -- , time-locale-compat + +executable args-example + import: lang + main-is: args-example.hs + build-depends: + base >=3 && <5 + , ansi-wl-pprint + , heredoc + , optparse-applicative diff --git a/hscrtmpl.hs b/hscrtmpl.hs --- a/hscrtmpl.hs +++ b/hscrtmpl.hs @@ -1,6 +1,9 @@ #! /usr/bin/env stack {- stack runghc -} +-- If you need a specific resolver, do this: +-- stack --resolver lts-7.8 runghc + {- No stack? Use this #! instead of the two lines above: #! /usr/bin/env runhaskell -} @@ -25,10 +28,12 @@ Dino Morelli https://github.com/dino-/hscrtmpl - version: 1.6 + version: 2.0 2023-06-27 -} import Control.Monad +import Data.List +import Data.Maybe import Data.Time import Data.Time.Format ( defaultTimeLocale ) -- Or use time-locale-compat for backwards compatibility with GHC < 7.10 @@ -70,8 +75,21 @@ -- environment variables (System.Environment) + + -- This will exit with a message and failure code if the variable doesn't exist! putStrLn =<< getEnv "SHELL" -- echo $SHELL + -- To handle unset variables, use lookupEnv :: String -> IO (Maybe String) + + -- someValue <- maybe someValue="${SOMEVAR:?Error: SOMEVAR not set}" + -- (die "Error: SOMEVAR is not set") + -- pure =<< lookupEnv "SOMEVAR" + + someValue <- fromMaybe "default value" -- someValue="${SOMEVAR:-default value}" + <$> lookupEnv "SOMEVAR" + putStrLn someValue + + -- arguments (System.Environment) --(arg1 : arg2 : _) <- getArgs -- arg1=$1 ; arg2=$2 @@ -79,6 +97,9 @@ printf "The %s is %d\n" -- S="answer" ; D=42 "answer" (42::Int) -- echo "The $S is $D" + -- sequence expressions + -- [1..10] -- {1..10} + -- execution, exit code (System.Process) ec <- system "ls -l" -- ls -l print ec -- echo $? @@ -147,14 +168,18 @@ exitBool = exitWith . toExitCode -{- This is similar to the for/in/do/done construct in bash with an - important difference. This action evaluates to ExitFailure 1 if - *any* of the command executions fails. In bash you only get the - exit code of the last one. +{- This is similar to the for/in/do/done construct in bash with an important + difference. This action evaluates to the "worst" exit code of all IO actions + that are passed after they are evaluated. -} -forSystem :: [String] -> IO ExitCode -forSystem cs = do - ecs <- mapM system cs - return $ case all (== ExitSuccess) ecs of - True -> ExitSuccess - False -> ExitFailure 1 +sequenceWorstEC :: [IO ExitCode] -> IO ExitCode +sequenceWorstEC as = + fromMaybe ExitSuccess . listToMaybe . reverse . sort <$> sequence as + + +{- This is similar to the for/in/do/done construct in bash with an important + difference. This action evaluates to the "worst" exit code of all shell + commands that are passed after they are evaluated. +-} +systemWorstEC :: [String] -> IO ExitCode +systemWorstEC = sequenceWorstEC . map system diff --git a/package.yaml b/package.yaml deleted file mode 100644 --- a/package.yaml +++ /dev/null @@ -1,39 +0,0 @@ -name: hscrtmpl -version: '1.6' -synopsis: Haskell shell script template -description: A template for writing shell scripts in Haskell. Contains some useful functions and examples of things commonly done in bash. -license: ISC -author: Dino Morelli -maintainer: dino@ui3.info -copyright: 2018 Dino Morelli -category: Application, Console, Scripting -extra-source-files: -- changelog.md -- .gitignore -- README.md -- package.yaml -- stack.yaml - -github: dino-/hscrtmpl - -ghc-options: -- -fwarn-tabs -- -Wall -- -Wcompat -- -Wincomplete-record-updates -- -Wincomplete-uni-patterns -- -Wredundant-constraints - -# Hey! hscrtmpl.hs is a *script*, you don't have to build it unless -# you want to have a binary! -executables: - hscrtmpl: - main: hscrtmpl.hs - dependencies: - - base >=3 && <5 - - directory - - filepath - - process - # - regex-compat - - time - # - time-locale-compat diff --git a/stack.yaml b/stack.yaml --- a/stack.yaml +++ b/stack.yaml @@ -1,4 +1,4 @@ -resolver: lts-12.11 +resolver: lts-16.11 packages: - '.'