mirror of
https://github.com/fish-shell/fish-shell.git
synced 2024-11-24 04:22:55 +08:00
43 lines
1.6 KiB
Plaintext
43 lines
1.6 KiB
Plaintext
\section case case - conditionally execute a block of commands
|
|
|
|
\subsection case-synopsis Synopsis
|
|
\fish{synopsis}
|
|
switch VALUE; [case [WILDCARD...]; [COMMANDS...]; ...] end
|
|
\endfish
|
|
|
|
\subsection case-description Description
|
|
|
|
`switch` performs one of several blocks of commands, depending on whether a specified value equals one of several wildcarded values. `case` is used together with the `switch` statement in order to determine which block should be executed.
|
|
|
|
Each `case` command is given one or more parameters. The first `case` command with a parameter that matches the string specified in the switch command will be evaluated. `case` parameters may contain wildcards. These need to be escaped or quoted in order to avoid regular wildcard expansion using filenames.
|
|
|
|
Note that fish does not fall through on case statements. Only the first matching case is executed.
|
|
|
|
Note that command substitutions in a case statement will be evaluated even if its body is not taken. All substitutions, including command substitutions, must be performed before the value can be compared against the parameter.
|
|
|
|
|
|
\subsection case-example Example
|
|
|
|
If the variable \$animal contains the name of an animal, the following
|
|
code would attempt to classify it:
|
|
|
|
\fish
|
|
switch $animal
|
|
case cat
|
|
echo evil
|
|
case wolf dog human moose dolphin whale
|
|
echo mammal
|
|
case duck goose albatross
|
|
echo bird
|
|
case shark trout stingray
|
|
echo fish
|
|
# Note that the next case has a wildcard which is quoted
|
|
case '*'
|
|
echo I have no idea what a $animal is
|
|
end
|
|
\endfish
|
|
|
|
If the above code was run with `$animal` set to `whale`, the output
|
|
would be `mammal`.
|
|
|