fish-shell/doc_src/case.txt
2014-09-03 14:43:25 +01:00

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\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`.