syntax ambiguities.

David Ungar David.Ungar at Eng.Sun.COM
Mon Sep 2 18:52:13 UTC 1996

Do you know that there is a Self 4.0?
It is available at our WEB site (
Maybe the manual is clearer.

Anyway here are the specific answers (hope they help):

     (| mySlot = ( randomNumber ) |)

This creates an object with one slot, "mySlot" containing
a method that sends randomNumber to self.
Informal rule: slot initializers enclosed in parens parse as methods.

aVar: ( randomNumber )

sends random Number to self and then sends aVar to self with the result
as its argument.

Rule: in the body of a method, parens are just for grouping.

Finally: is always parsed as a resend.

If you want a statement separator, you must leave a space (I think).
(foo. bar)

Rule: always leave a space (or newline, etc)
after a period used as a statement separator.

Good luck!

At 3:16 PM 9/2/96, Pierre De Pascale wrote:
>Hello selfer's,
>I have read the self 3.0 reference manual and stopped at the appendix
>where the syntax of the self language was presented. In particular the
>syntax presented is highly ambiguous, but a small foot-note says that
>the ambiguities are resolved using standard precedence techniques.
>But I still got some problems:
>1. when you initialize a slot. How do you determine if it is a method
>or a simple value ? for example:
>        (| mySlot = ( randomNumber ) |)
>what is the meaning of the mySlot initialization: do I initialize
>mySlot with a one-time call to randomNumber (i.e. mySlot is a value
>slot) or mySlot returns a new randomNumber everytime (i.e mySlot is a
>method) ?
>2. a same kind of ambiguities appears in expressions: what is the
>meaning of this expression ?
>        aVariable: ( randomNumber )
>Do I initialize aVariable with one random number, in this case () are
>for precedence reason, or with the object "(randomNumber)", in this
>case a method object.
>3. how can you detect a resend ? for example:
>        myResendSlot.resendMethod
>This could be interpreted as a directed resend or two expressions
>consisting of two method sends, one myResendSlot and one
>resendMethod. How do you make the difference ? is there a runtime
>decision of the meaning ?
>It may be possible that those issues were already discussed in this
>mailing list. Since I subscribed only lately I was lazy enough not to
>check the past issues. Just tell me if I need to kick myself :^)
>- Pierre.

-- Dave

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