すぐ忘れるfish script syntax

これは備忘録

更新予定：随時

script arguments

コマンドラインから与えられた引数の値は$argv配列（indexは1から始まる）を参照することで得られる。

argv, an array of arguments to the shell or function. argv is only defined when inside a function call, or if fish was invoked with a list of arguments, like fish myscript.fish foo bar. This variable can be changed by the user.

"Special variables" / http://fishshell.com/docs/current/index.html

hoge.fish

#!/usr/bin/env

echo $argv[1]

$ ./hoge.fish "fuga"
fuga

loop with command

コマンド実行結果を元にループ処理する場合

• https://fishshell.com/docs/current/commands.html#string
• http://stackoverflow.com/questions/19638400/fish-equivalent-to-for-loop-with-evaluation

loop.fish

#!/usr/bin/env fish

for i in (ls *.mp4)
    mv $i (string replace .mp4 .m4a $i)
end

$ ls *.mp4
hoge.mp4
fuga.mp4
bar.mp4

$ ./loop.fish

$ ls *.m4a
hoge.m4a
fuga.m4a
bar.m4a

上記の処理に限っては、Finderだけで一括変換できるが、わかりやすい例として挙げておく。

Operators for files and directories

下記の-eんとこのスイッチリスト

if test -e /var/path/hoge.log
 echo 'available'
end

-b FILE returns true if FILE is a block device.
-c FILE returns true if FILE is a character device.
-d FILE returns true if FILE is a directory.
-e FILE returns true if FILE exists.
-f FILE returns true if FILE is a regular file.
-g FILE returns true if FILE has the set-group-ID bit set.
-G FILE returns true if FILE exists and has the same group ID as the current user.
-L FILE returns true if FILE is a symbolic link.
-O FILE returns true if FILE exists and is owned by the current user.
-p FILE returns true if FILE is a named pipe.
-r FILE returns true if FILE is marked as readable.
-s FILE returns true if the size of FILE is greater than zero.
-S FILE returns true if FILE is a socket.
-t FD returns true if the file descriptor FD is a terminal (TTY).
-u FILE returns true if FILE has the set-user-ID bit set.
-w FILE returns true if FILE is marked as writable; note that this does not check if the filesystem is read-only.
-x FILE returns true if FILE is marked as executable.