diff --git a/LICENSE b/LICENSE new file mode 100644 --- /dev/null +++ b/LICENSE @@ -0,0 +1,31 @@ +Copyright 2012 Roel van Dijk + +All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are +met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + + * Redistributions in binary form must reproduce the above + copyright notice, this list of conditions and the following + disclaimer in the documentation and/or other materials provided + with the distribution. + + * The name of Roel van Dijk and the names of contributors may NOT + be used to endorse or promote products derived from this + software without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/README.markdown b/README.markdown new file mode 100644 --- /dev/null +++ b/README.markdown 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/src/System/ProgressBar.hs b/src/System/ProgressBar.hs new file mode 100644 --- /dev/null +++ b/src/System/ProgressBar.hs @@ -0,0 +1,149 @@ +{-# LANGUAGE NoImplicitPrelude, PackageImports, UnicodeSyntax #-} + +module System.ProgressBar + ( -- * Progress bars + progressBar + , mkProgressBar + -- * Labels + , Label + , noLabel + , msg + , percentage + , exact + ) where + +import "base" Data.Bool ( otherwise ) +import "base" Data.Function ( ($) ) +import "base" Data.List ( null, length, genericLength, genericReplicate ) +import "base" Data.Ord ( min, max ) +import "base" Data.Ratio ( (%) ) +import "base" Data.String ( String ) +import "base" Prelude ( (+), (-), round, floor ) +import "base" System.IO ( IO, putStr, putChar ) +import "base" Text.Printf ( printf ) +import "base" Text.Show ( show ) +import "base-unicode-symbols" Data.Bool.Unicode ( (∧) ) +import "base-unicode-symbols" Data.Eq.Unicode ( (≢) ) +import "base-unicode-symbols" Prelude.Unicode ( ℤ, ℚ, (⋅) ) + + +-- | Print a progress bar +-- +-- Erases the current line! (by outputting '\r') Does not print a +-- newline '\n'. Subsequent invocations will overwrite the previous +-- output. +-- +-- Remember to set the correct buffering mode for stdout: +-- +-- > import System.IO ( hSetBuffering, BufferMode(NoBuffering), stdout ) +-- > hSetBuffering stdout NoBuffering +progressBar ∷ Label -- ^ Prefixed label. + → Label -- ^ Postfixed label. + → ℤ -- ^ Total progress bar width in characters. + → ℤ -- ^ Amount of work completed. + → ℤ -- ^ Total amount of work. + → IO () +progressBar mkPreLabel mkPostLabel width todo done = do + putChar '\r' + putStr $ mkProgressBar mkPreLabel mkPostLabel width todo done + +-- | Renders a progress bar +-- +-- >>> mkProgressBar (msg "Working") percentage 40 30 100 +-- "Working [=======>.................] 30%" +mkProgressBar ∷ Label -- ^ Prefixed label. + → Label -- ^ Postfixed label. + → ℤ -- ^ Total progress bar width in characters. + → ℤ -- ^ Amount of work completed. + → ℤ -- ^ Total amount of work. + → String +mkProgressBar mkPreLabel mkPostLabel width todo done = + printf "%s%s[%s%s%s]%s%s" + preLabel + prePad + (genericReplicate completed '=') + (if remaining ≢ 0 ∧ completed ≢ 0 then ">" else "") + (genericReplicate (remaining - if completed ≢ 0 then 1 else 0) + '.' + ) + postPad + postLabel + where + -- Amount of work completed. + fraction ∷ ℚ + fraction | done ≢ 0 = todo % done + | otherwise = 0 % 1 + + -- Amount of characters available to visualize the progress. + effectiveWidth = max 0 $ width - usedSpace + usedSpace = 2 + genericLength preLabel + + genericLength postLabel + + genericLength prePad + + genericLength postPad + + -- Number of characters needed to represent the amount of work + -- that is completed. Note that this can not always be represented + -- by an integer. + numCompletedChars ∷ ℚ + numCompletedChars = fraction ⋅ (effectiveWidth % 1) + + completed, remaining ∷ ℤ + completed = min effectiveWidth $ floor numCompletedChars + remaining = effectiveWidth - completed + + preLabel, postLabel ∷ String + preLabel = mkPreLabel todo done + postLabel = mkPostLabel todo done + + prePad, postPad ∷ String + prePad = pad preLabel + postPad = pad postLabel + + pad ∷ String → String + pad s | null s = "" + | otherwise = " " + + +-- | A label that can be pre- or postfixed to a progress bar. +type Label = ℤ → ℤ → String + +-- | The empty label. +-- +-- >>> noLabel 30 100 +-- "" +noLabel ∷ Label +noLabel = msg "" + +-- | A label consisting of a static string. +-- +-- >>> msg "foo" 30 100 +-- "foo" +msg ∷ String → Label +msg s _ _ = s + +-- | A label which displays the progress as a percentage. +-- +-- Constant width property: +-- ∀ d t : ℕ. d ≤ t → length (percentage d t) ≡ 4 +-- +-- >>> percentage 30 100 +-- " 30%" + +-- ∀ d t : ℕ. d ≤ t → length (percentage d t) ≡ 3 +percentage ∷ Label +percentage done todo = printf "%3i%%" (round (done % todo ⋅ 100) ∷ ℤ) + +-- | A label which displays the progress as a fraction of the total +-- amount of work. +-- +-- Equal width property: +-- ∀ d₁ d₂ t : ℕ. d₁ ≤ d₂ ≤ t → length (exact d₁ t) ≡ length (exact d₂ t) +-- +-- >>> exact 30 100 +-- " 30/100" + +-- ∀ d₁ d₂ t : ℕ. d₁ ≤ d₂ ≤ t → length (exact d₁ t) ≡ length (exact d₂ t) +exact ∷ Label +exact done total = printf "%*i/%s" (length totalStr) done totalStr + where + totalStr = show total diff --git a/terminal-progress-bar.cabal b/terminal-progress-bar.cabal new file mode 100644 --- /dev/null +++ b/terminal-progress-bar.cabal @@ -0,0 +1,71 @@ +name: terminal-progress-bar +version: 0.0.1 +cabal-version: >=1.8 +build-type: Simple +stability: provisional +author: Roel van Dijk +maintainer: Roel van Dijk +copyright: 2012 Roel van Dijk +license: BSD3 +license-file: LICENSE +category: System, User Interfaces +homepage: https://github.com/roelvandijk/terminal-progress-bar +bug-reports: https://github.com/roelvandijk/terminal-progress-bar/issues +synopsis: A simple progress bar in the terminal +description: + A progress bar is used to convey the progress of a task. This + package implements a very simple textual progress bar. + . + See the module 'System.ProgressBar' on how to use the progress bar + or build the package with the -fexample flag for a small example + program. + . + The animated progress bar depends entirely on the interpretation of + the carriage return character (\'\r\'). If your terminal interprets + it as something else then "move cursor to beginning of line", the + animation won't work. + . + Note: Due to a bug in \"cabal haddock\" you will have to manually + uncomment the example section in the cabal file. But uncommenting + that section will result in \"cabal haddock\" failing. + +extra-source-files: LICENSE, README.markdown + +source-repository head + type: git + location: git://github.com/roelvandijk/terminal-progress-bar.git + +flag example + description: Build a small example program. + default: False + +library + hs-source-dirs: src + build-depends: base >= 3.0.3.1 && < 4.6 + , base-unicode-symbols >= 0.2.2.3 && < 0.3 + exposed-modules: System.ProgressBar + ghc-options: -Wall + +test-suite test-terminal-progress-bar + type: exitcode-stdio-1.0 + main-is: test.hs + hs-source-dirs: test + ghc-options: -Wall + build-depends: base >= 3.0.3.1 && < 4.6 + , base-unicode-symbols >= 0.2.2.3 && < 0.3 + , HUnit >= 1.2.4.2 && < 1.3 + , terminal-progress-bar == 0.0.1 + , test-framework >= 0.3.3 && < 0.5 + , test-framework-hunit >= 0.2.6 && < 0.3 + +-- executable example +-- main-is: example.hs +-- hs-source-dirs: . +-- if flag(example) +-- build-depends: base >= 3.0.3.1 && < 4.6 +-- , base-unicode-symbols >= 0.2.2.3 && < 0.3 +-- , terminal-progress-bar == 0.0.1 +-- buildable: True +-- else +-- buildable: False +