Self Playground

Transcript

Results appear here. Every run shares one world, so objects you add to the lobby stay until you press New world.

3 + 4 * 2: Messages, not operators. Binary messages go left to right: this is 14.
'abc' reverse size: Unary messages bind tightest, then binary, then keyword.
v at: 0 Put: 'x': A keyword message. Every part after the first starts with a capital.
(| x <- 1. y = 2. sum = ( x + y ) |): An object: an assignable slot, a constant slot and a method.
parent* = traits clonable: A star makes a parent slot. Messages the object doesn't understand go to its parents.
dog copy: No classes. New objects are copies of a prototype.
| a. b | a: 3.: Locals between bars. a: 3 is a message that assigns.
[| :x | x * 2 ] value: 21: A block: a closure. ifTrue:False: is a message that takes blocks.
resend.speak: Run the inherited speak, like super.
lobby _AddSlots: (| dog = … |): Add slots to a live object. The lobby is where names like dog live.
x printLine: Print to the transcript. (reflect: x) names lists slots.
"a comment": Comments go in double quotes; strings in single quotes.

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