[Newbies] Simple Precedence question

Randal L. Schwartz merlyn at stonehenge.com
Wed Feb 13 02:26:25 UTC 2008


>>>>> "Jeffrey" == Jeffrey Straszheim <jstraszheim at comcast.net> writes:

Jeffrey> So, I'm learning Smalltalk for the first time, and I have a very
Jeffrey> simple question regarding the precedence of the cascade operator.

Jeffrey> So, in this expression:

Jeffrey>  self something: anObject selector ; anotherSelector.

Jeffrey> Is the target of *anotherSelector* anObject, or self?

The way to read ";" is that you're replacing the last message
send of what precedes it with what follows it.  So let's see
the order there:

    t1 := anObject selector.
    t2 := self something: t1.

That should make sense.  Now for the cascade...  we do another
message send to whatever the most recent *receiver* was.  In this
case, "self":

    t3 := self anotherSelector.

And the overall value would be t3, if anyone looked at it.

-- 
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