Function Repository Resource:

StringSwitch

Switch but for strings

Contributed by: Michael Sollami

ResourceFunction["StringSwitch"][string,form₁,value₁,form₂,value₂,…]

compares string with each of the patterns form_i in turn, evaluates, and returns the value_i corresponding to the first match found.

Details and Options

ResourceFunction["StringSwitch"] uses StringMatchQ to compare the first argument to the form_i, rather than MatchQ.

The catch-all default form should be BlankNullSequence.

Switch on a string, just like you have always wanted to:

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Switch using any valid string pattern:

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$ResourceFunction["StringSwitch"][#, NumberString .., "numbers", "t" ~~ __ ~~ "a", "genius"] & /@ {"tesla", "1234"}$

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Provide a default case:

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$ResourceFunction["StringSwitch"][#, x__ /; StringStartsQ[x, "x"], "Starts with x", ___, "Doesn't start with x"] & /@ {"xyz", "zyx"}$

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The first argument must be a String:

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StringSwitch takes an odd number of arguments:

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