[Edu-sig] Freedom: some Smalltalk history and Python implications

[Arthur]

kirby urner wrote:

>>         ifTrue:[^self scalarAdd: aNumericObject]
>>         ifFalse:[^self vectorAdd: aNumericObject].
>>
>>and then:
>>
>>Vector>>scalarAdd: aNumber
>>     x := x + aNumber.
>>     y := y + aNumber.
>>     z := z + aNumber.
>>
>>Vector>>vectorAdd: aVector
>>     x := x + aVector x.
>>     y := y + aVector y.
>>     z := z + aVector z.
>>
>>The case analysis in Vector>>+ can be quite annoying so often there are
>>other techniques (like double-dispatching) used to implement the proper
>>coercion. The common technique currently used by Squeak coerces based on
>>generality, so to implement the "reverse" set of operations you'd do, e.g.,
>>
>>Vector>>adaptToNumber: aNumber andSend: aSymbol
>>     "If I am involved in arithmetic with a scalar, return a Vector of
>>     the results of each element combined with the scalar in that
>>     expression."
>>     ^Vector
>>         x: (x perform: aSymbol with: aNumber)
>>         y: (y perform: aSymbol with: aNumber)
>>         z: (z perform: aSymbol with: aNumber)
>>    
>>
At what point does it become appropriate to expect this conversation to 
move over to "Squeakland" - where kids who are different than I was are 
treated without condescension.

Art