https://forum.world.st/How-does-Boolean-ifTrue-work-tp4920873p4920874.html
> On 31 Oct 2016, at 14:17, CodeDmitry <
[hidden email]> wrote:
>
> I am looking at
>
> ifTrue: alternativeBlock
> "If the receiver is false (i.e., the condition is false), then the value is
> the
> false alternative, which is nil. Otherwise answer the result of evaluating
> the argument, alternativeBlock. Create an error notification if the
> receiver is nonBoolean. Execution does not actually reach here because
> the expression is compiled in-line."
>
> self subclassResponsibility
>
> In order to perform the block, ifTrue must somehow end up evaluating the
> block, but this code only sends a subclassResponsibility message to itself
> and implicitly returns itself.
>
> Where does the block actually get evaluated?
In the sub classes of Boolean, True and False. Have a look at ALL implementors of #ifTrue: or #ifFalse:
There is only one instance of True, the constant true, same for False and false.