image-watcher

Display an image and update it when the file changes.

$ image-watcher --help
Usage: image-watcher FILE
  Display an image and update it when the file changes

Available options:
  FILE                     Image file to watch and display
  -h,--help                Show this help text

Especially useful in combination with a program like ghcid or fswatcher which runs a command when your code changes. Write a function which renders your image description to a file, and configure that program to run that function whenever you edit that image description. Tada! You now have a live preview for that image description.

For completeness, here's the code I use in the above demo.

import Diagrams.Prelude
import Diagrams.Backend.Cairo.CmdLine
import System.Environment

myDiagram :: Diagram B
myDiagram = circle 180 # fc aliceblue

main :: IO ()
main = do
  withArgs ["--output", "out.png"] $ do
    mainWith myDiagram

I then use vim in one terminal, ghcid --test=main in the other, and image-watcher out.png in the background.