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3a23fdf359
Includes harmonizing the display of options and arguments, standardising terminology, using the envvar directive more broadly, adding help options to all commands that support them, simplifying some language, and tidying up multiple formatting issues. string documentation is not changed.
48 lines
1.6 KiB
ReStructuredText
48 lines
1.6 KiB
ReStructuredText
.. _cmd-switch:
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switch - conditionally execute a block of commands
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==================================================
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Synopsis
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--------
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.. synopsis::
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switch VALUE; [case [GLOB ...]; [COMMANDS ...]; ...] end
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Description
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-----------
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``switch`` performs one of several blocks of commands, depending on whether a specified value equals one of several globbed values. ``case`` is used together with the ``switch`` statement in order to determine which block should be executed.
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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 globs. These need to be escaped or quoted in order to avoid regular glob expansion using filenames.
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Note that fish does not fall through on case statements. Only the first matching case is executed.
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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.
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Example
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-------
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If the variable :envvar:`animal` contains the name of an animal, the following code would attempt to classify it:
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::
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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 $animal is
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end
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If the above code was run with ``$animal`` set to ``whale``, the output
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would be ``mammal``.
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