- Problem with pointer semantics

From: [at]} <Rex>
Date: Mon, 19 Jun 2006 14:20:56 -0500

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        This has to be a pretty standard problem in computer science, and it's not limited to BlackBox. Is there a good way to handle the following ambiguity? The problem is that you don't know by looking at an assignment statement what the results will be.

        My own method is pretty ugly: I use Hungarian notation. Please tell me there's a better way. Thanks.

Rex Couture

==========
VAR
        a, b: POINTER TO ARRAY OF INTEGER;
        x, y: ARRAY 2 OF INTEGER;

NEW( a, 2); NEW( b, 2);
a[1]:= 1; b[1]:= 2;
x[1]:= 1; y[1]:= 2;

b:= a;
y:= x; (* not an equivalent statement *)

b[1]:= 5; (* a[1] = 5 *)
y[1]:= 5; (* x[1] = 1 *)

--- BlackBox
--- send subject HELP or UNSUBSCRIBE to blackbox{([at]})nowhere.xy



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Received on Mon Jun 19 2006 - 21:20:56 UTC