snippet-0.1.0.0: README.lhs

# Snippet

## Usage

<!--

```haskell
module Main (main) where
import Text.Markdown.Unlit ()
```

-->

```haskell
import Prelude

import Data.Foldable (traverse_)
import Prettyprinter (reAnnotate)
import Prettyprinter.Render.Terminal (putDoc)
import Snippet
import Snippet.Pretty

main :: IO ()
main = do
  let
    region = Region
      { startLine = 24
      , endLine = Just 36
      , startColumn = Just 8
      , endColumn = Nothing
      }

  -- Returns Nothing if file is missing/empty or region is invalid
  mSnippet <- snippetFromFile region "README.md"

  traverse_ (putDoc . reAnnotate annToAnsi . prettySnippet) mSnippet
```

The above `Region` focuses just the body of the `do` block in this file.
Rendering it with the default `annToAnsi` looks like:

![](./example.png)

Supplying an alternative `annToAnsi` function is how you can adjust colors.

> [!NOTE]
>
> The simple `putDoc` function is fine for this toy example because the lines
> are narrow enough not to break. In real usage, you should implement your own
> layout using an [`Unbounded` `PageWidth`][unbounded].

[unbounded]: https://hackage-content.haskell.org/package/prettyprinter-1.7.2/docs/Prettyprinter.html#t:PageWidth

## License

This package is licensed AGPLv3. See [COPYING](./COPYING).