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From: bobo@avogadro.arc.nasa.gov (Mark Friedman)
Subject: Re: what is a pattern?
In-Reply-To: olevi@daimi.aau.dk's message of 8 Sep 1994 15:41:16 GMT
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References: <34n5ad$36s@gort.oit.umass.edu> <34nbas$a8d@belfort.daimi.aau.dk>
Date: Thu, 8 Sep 1994 18:35:48 GMT

In article <34nbas$a8d@belfort.daimi.aau.dk> olevi@daimi.aau.dk (Ole
Villumsen) writes:

     multiply: (# a,b: @integer;
	       enter (a,b)
	       exit a*b
	       #);

   In Beta a call to multiply might look like:
	       (9,13) -> &multiply -> &putInt;
   (putInt is a procedure that writes the result on the screen.)

     stack: (# content: [100] @integer;
	       currentSize: @integer;
	       push: (# e: @integer;
		     enter e
		     do currentSize+1 -> currentSize;
			e -> content[currentSize];
		     #);
	       empty: (# exit (currentSize=0) #);
	       pop: (# e: @integer;
		    do content[currentSize] -> e;
		       currentSize-1 -> currentSize;
		    exit e
		    #);
	    #);

So far this makes patterns look pretty much like closures. How do
they differ?

-Mark
-- 
Mark Friedman
NASA-Ames Research Center
MS 269-2
Moffett Field, CA 94035-1000

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