Smalltalk Variadic functions

Question

Does Smalltalk(especially Squeak/Pharo) have some form of variadic functions?

I was just reading about the power of designing your own control statments in smalltalk and while I'm a big fan of ifTrue: ifFalse: I was having a hard time coming up with a good way to implement arbitrary if,if else, if else,...,else statements thinking how useful Variadic functions those would be for implementing case statements. Something like

false class

ifTrue: aBlock (... elseIf: aBoolean then: aSecondBlock ...) else: aLastBlock

vArgList pairsDo: [:x :y| x ifTrue:[^ (y value)] ].
^ aLastBlock

Answer 1

Smalltalk's keyword-like syntax for method calls inherently defines the arity of the method. There's no &rest pattern like in Common Lisp.

You can of course have a method take a list, like BlockClosure>>valueWithArguments: but that's hardly the same thing.

You might modify Compiler to support variadic method calls. Maybe the call would simply have with: between each of the variables:

(condition) ifTrue: aBlock elseIf: aBoolean with: aSecondBlock with: anotherBoolean with: aThirdBlock

Answer 2

You can use the #caseOf:otherwise: message. Look for some sender of this message for some example.

But anyway if you want to use case statement you are not following the smalltalk-way-of-doing-things. Tell us what you want to achieve with your case statement so that we can show you some cleaner way to do it.