lens-filesystem: Lens interface for your filesystem; still a bit experimental

[ bsd3, control, library ] [ Propose Tags ]

Please see the README on GitHub at https://github.com/ChrisPenner/lens-fs#readme

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Versions [faq],,
Change log ChangeLog.md
Dependencies base (>=4.7 && <5), directory, filepath, lens, lens-action [details]
License BSD-3-Clause
Copyright 2019 Chris Penner
Author Chris Penner
Maintainer christopher.penner@gmail.com
Category Control
Home page https://github.com/ChrisPenner/lens-filesystem
Bug tracker https://github.com/ChrisPenner/lens-filesystem/issues
Source repo head: git clone https://github.com/ChrisPenner/lens-filesystem
Uploaded by ChrisPenner at 2020-10-21T04:00:50Z
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Downloads 430 total (3 in the last 30 days)
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Maintainer's Corner

For package maintainers and hackage trustees

Readme for lens-filesystem-

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A lensy style interface to your filesystem.

This is pretty experimental; I wouldn't recommend using it in production code at the moment; Using the read-only operations should be fine, but I'd strongly recommend doing lots of testing with print before you run destructive filesystem operations.

This library is meant to be used in conjunction with the lens-action library.

The interface to this package could change at any time.


Many of the combinators you see here come from `lens-action`.

-- Find all files in ~ or ~/config with a .vim or .conf extension
>>> "/Users/chris" ^!! including (path "config") . ls . traversed . exts ["vim", "conf"]

-- Check whether a filename is a dotfile
>>> let isDotfile = has (filename . _head . only '.')
-- Crawl a filetree according to a given fold, 
-- e.g. crawl all dirs that aren't dotfiles (a.k.a. .git, .stack-work)
>>> "." ^!! crawling (ls'ed . dirs . filtered (not . isDotfile))
[ "." , "./app" , "./test" , "./src" , "./src/Control"
, "./src/Control/Lens", "./src/Control/Lens/FileSystem"]

-- Crawl ALL files in "src" collecting "*.hs" files, then make file paths absolute
>>> "src" ^!! crawled . exts ["hs"] . absolute
[ "/Users/chris/dev/lens-fs/src/Control/Lens/FileSystem/Combinators.hs"
, "/Users/chris/dev/lens-fs/src/Control/Lens/FileSystem.hs" ]

-- Find all executables in the 'scripts' directory and copy them to bin
>>> "scripts" ^! crawled . withPerms [executable] . act (`copyFile` "/Users/chris/bin")

-- Read all markdown files and get their contents with filename
>>> "./test" ^!! crawled . exts ["md"] . contents . withIndex

See more examples in the tests