[Oberon] Anonymous procedure?

[Jörg]

Answers:
1) Lyall
No, you cannot write    Append := PROCEDURE BEGIN END;

You always have to add an empty procedure
   PROCEDURE Empty; END Empty;
and then assign   Append := Empty;

2) Wojtek
Append := NIL and Append := Empty are not the same. In the first case, calling Append will result in a runtime error. In the latter case calling Append will do nothing.

Jörg


Am 18.01.19, 03:36 schrieb "Oberon im Auftrag von Skulski, Wojciech" <oberon-bounces at lists.inf.ethz.ch im Auftrag von skulski at pas.rochester.edu>:

    Peter: 
    
    >Can an anonymous procedure be assigned to a procedure
    >variable in any Oberon language.  Illustrated hypothetically
    >by this.
    >(* Assign anonymous null procedure to Append. *)
    >PROCEDURE NullifyAppend*(); BEGIN Append := PROCEDURE BEGIN END END NullifyAppend;
    
    What is the motivation?
    
    If I am not mistaken, you can assign NIL, which becomes an anonymous procedure which stops the execution when called. Is this what you need?
    
    Wojtek
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