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