diff --git a/LICENSE b/LICENSE new file mode 100644 --- /dev/null +++ b/LICENSE @@ -0,0 +1,20 @@ +Copyright (c) 2015 Daniel Choi + +Permission is hereby granted, free of charge, to any person obtaining +a copy of this software and associated documentation files (the +"Software"), to deal in the Software without restriction, including +without limitation the rights to use, copy, modify, merge, publish, +distribute, sublicense, and/or sell copies of the Software, and to +permit persons to whom the Software is furnished to do so, subject to +the following conditions: + +The above copyright notice and this permission notice shall be included +in all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, +EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. +IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY +CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, +TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE +SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. diff --git a/Main.hs b/Main.hs new file mode 100644 --- /dev/null +++ b/Main.hs @@ -0,0 +1,106 @@ +{-# LANGUAGE OverloadedStrings #-} +module Main where + +import Data.Text (Text) +import qualified Data.Text as T +import qualified Data.Text.IO as T +import System.Environment (getArgs) +import Control.Applicative +import Data.List (transpose) +import Data.Monoid +import Options.Applicative + +data Options = Options { + matchMode :: MatchMode + , matchStrings :: [Text] + } deriving (Show) + +data MatchMode = Series | Alternatives deriving Show + +parseOpts :: Parser Options +parseOpts = Options + <$> flag Series Alternatives + (short 'a' <> long "alternatives" + <> help "Treat match strings as alternatives for alignment, like regex /(a|b|c)/.") + <*> ((T.words . T.pack) <$> + (argument str + (metavar "MATCH STRINGS" + <> help "The strings to align on, between a pair of single quotes"))) + +opts = info (helper <*> parseOpts) + (fullDesc <> progDesc "Align code text from STDIN on operators." + <> header "align" + <> footer "See https://github.com/danchoi/align for more info.") + +main = do + Options mode alignStrings <- execParser opts + input <- (T.lines . T.pack) <$> getContents + let result :: [Text] + result = + case mode of + Series -> foldl (\lines sep -> align lines sep) input alignStrings + Alternatives -> alignOnAlteratives alignStrings input + T.putStr . T.unlines $ result + +-- Aligning in standard Series mode +align :: [Text] -> Text -> [Text] +align lines alignString = + let lines' :: [[Text]] + lines' = map (splitOn alignString) lines + firstCol:rest = transpose lines' + firstCol' = adjustWidth alignString firstCol + lines'' = transpose (firstCol':rest) + in map T.concat lines'' + +-- split a line into two segments if it contains the alignstring, +-- and one if it doesn't +splitOn :: Text -> Text -> [Text] +splitOn alignString input = + let (x,y) = T.breakOn alignString input + in [z | z <- [x, trim alignString y], z /= mempty] + +-- | Makes column cells in a column the same width +-- Used for the standard Series mode. +adjustWidth :: Text -> [Text] -> [Text] +adjustWidth alignStr xs = + map maybeAdjust xs + where maxWidth = maximum $ map (T.length . T.stripEnd) $ xs + maybeAdjust :: Text -> Text + maybeAdjust cell = T.justifyLeft maxWidth ' ' . T.stripEnd $ cell + +alignOnAlteratives :: [Text] -> [Text] -> [Text] +alignOnAlteratives alts lines = + -- each row cell contains (Maybe alternative) that was split on + let lines' :: [[Text]] + lines' = map (splitOnAny alts) lines + firstCol:rest = transpose lines' + firstCol' = adjustWidth' firstCol + lines'' = transpose (firstCol':rest) + in map T.concat lines'' + +-- | adjust width of a column of cells +adjustWidth' :: [Text] -> [Text] +adjustWidth' xs = + map adj xs + where maxWidth = maximum $ map (T.length . T.stripEnd) xs + adj cell = T.justifyLeft maxWidth ' ' . T.stripEnd $ cell + + +-- | Attempts to split line on any of the alternatives +-- and returns the segments +splitOnAny :: [Text] -> Text -> [Text] +splitOnAny alts line = + let alts' = filter (`T.isInfixOf` line) alts + in if null alts' + then [line] + else let alt = head alts' + in splitOn alt line + +-- | strips whitespace around text but makes sure that it's left-padded with one space +trim :: Text -> Text -> Text +trim alignString s = + -- alignString will be on 1st elem of tuple: + let (x,y) = T.breakOnEnd alignString s + in T.cons ' ' + $ mconcat [T.strip x, " ", T.strip y] + diff --git a/README.md b/README.md new file mode 100644 --- /dev/null +++ b/README.md @@ -0,0 +1,123 @@ +# align + +Simple unix filter to align text on specified substrings. + +`align` can be run from inside Vim or other editors with custom key bindings to +align lines of code neatly on programming language operators like =>, ::, @=?, +=, +, etc. + +## Usage + +`align` has two modes: Series mode and Alternative mode. + +### Series mode + +Assume you want to align this text: + +input.sample: +``` + "parseKeyExpr" ~: [ObjectKey "item"] @=? parseKeyExpr "item" + , "ngEvalToString" ~: "apple" @=? ngEvalToString testContext1 "item" + , "ngEvalToString2" ~: "apple" @=? ngEvalToString testContext2 "item.name" +``` + +You can do so with this command: + + align '~: @=?' < input.sample + +which outputs: + +``` + "parseKeyExpr" ~: [ObjectKey "item"] @=? parseKeyExpr "item" + , "ngEvalToString" ~: "apple" @=? ngEvalToString testContext1 "item" + , "ngEvalToString2" ~: "apple" @=? ngEvalToString testContext2 "item.name" +``` + +`align` takes an argument list of strings to align the text and performs +the alignment operation on the text it gets from STDIN. + +`align` will only match each alignment string once, so if that string +occurs multiple times in a line, you need to specify it than many times +in the argument. + +### Alternative mode + +Assume you want to align this text: + +input2.sample: +``` +sendmailCustom :: FilePath -- ^ sendmail executable path + -> [String] -- ^ sendmail command-line options + -> L.ByteString -- ^ mail message as lazy bytestring + -> IO () +``` + +Here you want to align `::` and `->` in the same column position. To +do this use the `-a` flag: + + align -a -- '-> ::' < input2.sample + +(FYI you need to add the `--` argument to prevent the `->` string, which starts +with a dash, from being parsed as a command option.) + +This outputs: + +``` +sendmailCustom :: FilePath -- ^ sendmail executable path + -> [String] -- ^ sendmail command-line options + -> L.ByteString -- ^ mail message as lazy bytestring + -> IO () +``` + +You can also align the comment (beginning with `--`) by using a pipeline: + + cat input2.sample | align -a -- '-> ::' | align -- '--' + +which outputs: + +``` +sendmailCustom :: FilePath -- ^ sendmail executable path + -> [String] -- ^ sendmail command-line options + -> L.ByteString -- ^ mail message as lazy bytestring + -> IO () +``` + +## How to use align in Vim + +To use align from Vim, you can select some text, and then use a Vim +filter command: + + !align '~: @=?' + +For common alignment operations, you can make Vim commands and put them +in your `.vimrc`, e.g.: + +```vimscript +command! -range AlignHaskellTypeAnnotation :,!align '::' +vnoremap h :AlignHaskellTypeAnnotation + +command! -range AlignHaskellTest :,!align '~: @=?' +vnoremap H :AlignHaskellTest + +``` + +## Installation + +You must first have the Haskll platform installed on your system: + +* [Haskell platform](https://www.haskell.org/platform) + +`git clone` this project to a local directory. Then from that directory, +run this command: + +``` +cabal install +``` + +This will likely install the `align` executable in ~/.cabal/bin, which should be on your PATH. + + +## Author + +Daniel Choi + diff --git a/Setup.hs b/Setup.hs new file mode 100644 --- /dev/null +++ b/Setup.hs @@ -0,0 +1,2 @@ +import Distribution.Simple +main = defaultMain diff --git a/align-text.cabal b/align-text.cabal new file mode 100644 --- /dev/null +++ b/align-text.cabal @@ -0,0 +1,27 @@ +-- Initial align.cabal generated by cabal init. For further documentation, +-- see http://haskell.org/cabal/users-guide/ + +name: align-text +version: 0.1.0.0 +synopsis: A simple unix filter to align text on specified substrings +description: A simple unix filter to align text on specified substrings +homepage: https://github.com/danchoi/align-text +license: MIT +license-file: LICENSE +author: Daniel Choi +maintainer: dhchoi@gmail.com +-- copyright: +category: Text +build-type: Simple +-- extra-source-files: +cabal-version: >=1.10 + +executable align + main-is: Main.hs + -- other-modules: + -- other-extensions: + build-depends: base >=4.7 && <4.8 + , text + , optparse-applicative + -- hs-source-dirs: + default-language: Haskell2010 diff --git a/input.sample b/input.sample new file mode 100644 --- /dev/null +++ b/input.sample @@ -0,0 +1,3 @@ + "parseKeyExpr" ~: [ObjectKey "item"] @=? parseKeyExpr "item" + , "ngEvalToString" ~: "apple" @=? ngEvalToString testContext1 "item" + , "ngEvalToString2" ~: "apple" @=? ngEvalToString testContext2 "item.name"