Merge Request: #caseOf:otherwise: with arguments

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Merge Request: #caseOf:otherwise: with arguments

Christoph Thiede

This changeset makes it possible to accept an argument in the otherwise block of a #caseOf:otherwise: call.


Diff of the #caseOf:otherwise: implementation:

caseOf: aBlockAssociationCollection otherwise: aBlock

"The elements of aBlockAssociationCollection are associations between blocks.  Answer the evaluated value of the first association in aBlockAssociationCollection whose evaluated key equals the receiver.  If no match is found, answer the result of evaluating aBlock."


aBlockAssociationCollection associationsDo:

[:assoc | (assoc key value = self) ifTrue: [^assoc value value]].

- ^ aBlock value

+ ^ aBlock cull: self


"| z | z := {[#a]->[1+1]. ['b' asSymbol]->[2+2]. [#c]->[3+3]}. #b caseOf: z otherwise: [0]"

"| z | z := {[#a]->[1+1]. ['d' asSymbol]->[2+2]. [#c]->[3+3]}. #b caseOf: z otherwise: [0]"

"The following are compiled in-line:"

"#b caseOf: {[#a]->[1+1]. ['b' asSymbol]->[2+2]. [#c]->[3+3]} otherwise: [0]"

"#b caseOf: {[#a]->[1+1]. ['d' asSymbol]->[2+2]. [#c]->[3+3]} otherwise: [0]"

"#b caseOf: {[#a]->[1+1]. ['d' asSymbol]->[2+2]. [#c]->[3+3]} otherwise: [:x | x halt]"


Furthermore, the changeset includes a necessary modification of MessageNode >> #transformCase: so that the otherwise argument can be compiled in-line.

Last but not least, I wrote some tests for #caseOf:[otherwise:].


Please review!

(In a later change, it would be possible to allow arguments for the association key blocks as well. But I love short feedback loops, so let's assess this one first :-))


Best,

Christoph




#caseOf#otherwise# with arguments.1.cs (5K) Download Attachment
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