Is there a way to assign a value to an input string?

I was wondering if there was a way to assign a second value to an input that would actually be used in the function instead of the input value itself. Let me see if I can describe what I mean,

function [output] = fun(input)
'phrase' = 1
end
>>fun('phrase')
output = 1

What I'm trying to do is have Matlab recognize a certain input string and have it set its value to some other double value that can then be used in the function. Sort of like assigning a secret value to it that requires the input to be that specified string. I'm sorry if that doesn't make sense, I'm having a hard time finding the words for exactly what I'm trying to do. Can anyone help?

[KSSV]

REad about switch, strcmp.

[Brett Baxter]

Got it, thank you!