Surf your file system on Linux:
Dash through your file system on Windows:
Julia's REPL and its modes are superb. They also offer a variety of ways to interact with the underlying file system -- the cd("somedir") function, a full-blown shell mode, macro capabilities, etc. Yet all involve just a tiny bit more typing of (often shifted) chars, or a mode switch.
Shelly provides a modeless and minimal-keystroke way of navigating the file system with cd, ls, and ll, or dir on Windows. (Use lla, lsa, or dira to also show hidden files.) On Linux, some additional Unix shortcuts are available.
Shelly does not hack the REPL. Instead, it just uses show on custom types, and it overloads a special-case multiplication (multiply and conquer, if you will). Find out how it works below the examples.
Install with:
pkg> add Shelly
julia> using ShellyOr, to avoid name collisions, maybe just selectively import the ones you like:
julia> import Shelly: ll, lla, ls, lsa, df, ldf, ps1, cc, °, [Linux only->] head, tail, wc # or any subsetIn particular, ls might clash with FileJockey.jl's ls() function. But you can always create your own shortcut to it with myls = Shelly.ls.
Note: There is no need to import cd or cat -- learn why below.
Say our current directory is the "Shelly.jl" one:
# Note: - we are in Julia's native REPL mode
# - the output of 'll' here is written directly to the console
julia> ll
drwxr-xr-x 4 martin martin 4096 Jul 1 12:29 . 1cd
drwxr-xr-x 10 martin martin 4096 Jul 1 12:29 .. 2cd
drwxr-xr-x 2 martin martin 4096 Jul 1 12:29 src 3cd
-rw-r--r-- 1 martin martin 1062 Jul 1 12:29 LICENSE 4
-rw-r--r-- 1 martin martin 138 Jul 9 11:22 Project.toml 5
-rw-r--r-- 1 martin martin 5496 Jul 1 12:29 README.md 6
We can now, still in the Julia REPL mode, change the current dir to src via its index from the ll command:
julia> 3cd
julia> pwd() # the standard Julia function shows:
"/home/martin/Shelly.jl/src" # we have indeed moved!
Let's look around here:
julia> ll
drwxr-xr-x 2 martin martin 4096 Jul 1 12:29 . 1cd
drwxr-xr-x 4 martin martin 4096 Jul 1 12:29 .. 2cd
-rw-r--r-- 1 martin martin 7488 Jul 1 12:29 Shelly.jl 3
-rw-r--r-- 1 martin martin 426 Jul 1 12:29 Shelly.jl_base 4
-rw-r--r-- 1 martin martin 502 Jul 9 12:50 Shelly.jl_docs 5
-rw-r--r-- 1 martin martin 265 Jul 1 12:29 Shelly.jl_exports 6
And now move back up:
julia> 2cd
julia> ll
drwxr-xr-x 4 martin martin 4096 Jul 1 12:29 . 1cd
drwxr-xr-x 10 martin martin 4096 Jul 1 12:29 .. 2cd
drwxr-xr-x 2 martin martin 4096 Jul 1 12:29 src 3cd
-rw-r--r-- 1 martin martin 1062 Jul 1 12:29 LICENSE 4
-rw-r--r-- 1 martin martin 138 Jul 9 11:22 Project.toml 5
-rw-r--r-- 1 martin martin 5693 Jul 9 11:25 README.md 6
The same works with ls. To save space and be lighter on the eye, a °-suffix instead of cd denotes dirs. Both strings work when trying to change directory:
julia> ls
1° . 2° .. 3° src 4 LICENSE 5 Project.toml 6 README.md
julia> 3cd
julia> pwd()
"/home/martin/Shelly.jl/src"
julia> 2cd
julia> pwd()
"/home/martin/Shelly.jl"
julia> 3°
julia> pwd()
"/home/martin/Shelly.jl/src"
julia> 2°
julia> pwd()
"/home/martin/Shelly.jl"
There is even a third, prefix-based way to change dir via !:
julia> !2 # is same as '2cd' or '2°'
(Alas, it seems to be impossible to alias the ! operator for now..)
julia> dir
09-Jul-23 11:44 AM <DIR> . 1cd
09-Jul-23 11:44 AM <DIR> .. 2cd
09-Jul-23 11:40 AM 1,062 LICENSE 3
09-Jul-23 11:44 AM 138 Project.toml 4
09-Jul-23 11:44 AM 5,870 README.md 5
09-Jul-23 12:12 PM <DIR> src 6cd
julia> 6cd
julia> pwd()
"C:\\work\\Shelly.jl\\src"
(On Windows, ll = dir, while ls is the short variant.)
julia> ls
1° . 2° .. 3 Shelly.jl 4 Shelly.jl_base 5 Shelly.jl_docs 6 Shelly.jl_exports
julia> 3cat
module Shelly
using Base.Iterators
...
...
These would also work:
julia> 3head
..
julia> 3tail
..
julia> 3wc
..
We can show our mounts with ldf (df is also available, but not exported, as it can easily clash with some DataFrame variable):
julia> ldf
/dev/sdb 263174212 8247948 241488108 4% / -1cd
tmpfs 6448660 0 6448660 0% /mnt/wsl -2cd
tools 498750460 172976384 325774076 35% /init -3cd
To cd to a mount, use negative indices:
julia> -2cd
- You don't have to use
lsbefore running acdshortcut, especially if you remember the index 0cdgoes to your home directory2cdalways meanscd ..-- but because we want a shortcut for that shortcut, you can useccinstead!
The ll-commands just write stuff to stdout. But your can still recover this content via the pipe operator -- this will yield a string array:
julia> ll |> collect
As you'll gallivant around your file system more promiscuously now, you might want to tune the REPL prompt:
julia> ps1
Shelly.jl/::julia> # the new prompt shows the current dir now
-
Shortcuts like
lsandllare simple -- they are just values:struct ShortcutLs <: AbstractShortcut end const ls = ShortcutLs()The
Base.showmethod callsShelly.atshowfor allAbstractShortcuts, where the actuallsprinting takes place:atshow(_::ShortcutLs) = _ls()Note: following the above logic, you can easily define your own shortcuts!
-
Shortcuts that require an argument, like
cd, work differently.First, Julia provides a neat way of parsing multiplication without the
*operator:julia> x = 21 julia> 2x 42If x is of some new, custom type, we can override the multiplication operation:
Base.:*(i::Int64, _::SomeNewType) = ...But here we want to use the string
cd, which is an already-defined Julia function. Luckily, we don't even have to dispatch on functions in general, but we can dispatch on thecds singleton type as seen in:julia> typeof(cd) typeof(cd) (singleton type of function cd, subtype of Function)We can thus use:
Base.:*(i::Int64, _::typeof(cd)) = ShortcutCd(i)And underneath, the same logic as above is then at work:
atshow(x::ShortcutCd) = _cd(x.i)
0.9.0 list hidden files: lla/lsa==ls [-l] -a, and dira (thanks to @oheil !); ldf, root dir handling, and group-by-dirs on Windows; capture output via pipe; code re-org
0.8.1 Export ldf on Mac; minor doc update
0.8 df -> ldf
0.7 Doc update; dirs listed first on Linux; dir on Windows; exports; docstring; macOS fix
0.6 Initial version
more commands (pwd?) ...