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--* Date: Fri, 10 Jun 1994 19:27:35 -0400
--* From: Tony Kennedy <adk@ibm4.scri.fsu.edu>
--* Message-Id: <199406102327.AA109692@ibm4.scri.fsu.edu>
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--* Subject: [3] foamTag: Values is unhandled [etuple.as][A# version 34.6 for AIX RS/6000 (debug version)]

--@ Fixed  by:  PAB   Tue Jun 21 18:47:11 EDT 1994 
--@ Tested by:  object0.as 
--@ Summary:    convinced genfoam to accept embeddings in defines 

--+ A# version 34.6 for AIX RS/6000 (debug version)
--+ foamTag: Values is unhandled.
--+                in sc sy li pa ma ab ck sb ti gf of pb pl pc po
--+  Time    3.4 s  1 .5  1 .5  1 .5  0  0  1 74  4  2 .2 .2 10  0 %
--+  Alloc  3167 K .2 .4 .0 .7 .5 .3 .1 .0  1 81  3 .3  0  0  9 .0 %
--+  Free    764 K .1 .0 .0  3 .1 .9 .4 .0  1 47  3  2  0  0 32  0 %
--+
--+  Source  126 lines,  2217 lines per minute
--+  Store  2796 K pool, 3167K alloc - 764K free - 0K gc = 2403K final
--
-- etuple.as
--

#include "aslib"

macro SI == SingleInteger;

+++ `Tuple(T)' provides more functions for values of type `Tuple T'.
+++
+++ Author: ADK
+++ Date Created: 10-JUN-1994
+++ Keywords: tuple, homogeneous product, immutable

extend Tuple(T: Type): with {
	first: % -> T;
		++ first(t) extracts the first element of the tuple t.

	rest: % -> %;
		++ rest(t) returns a tuple of all the elements of the tuple t
		++ except for the first.

	export from T;
}
== add {
	macro Rep == Record(size: BSInt, values: BArr);

	import from Rep, Machine, SI, T;

	print("Instantiating domain Tuple(T)...")();

	first(t: %): T == get(T)(rep(t).values, 0);

	rest(t: %): % == {
		news: BSInt == prev(rep(t).size);
		newt: BArr == array(T)(0@BSInt pretend T, news);

		for i:SI in 0..(news::SI) repeat
			set!(T)(newt,
				i::BSInt,	
				get(T)(rep(t).values, next(i::BSInt)));
		per [news, newt]
		}
	}

-- Test

import from SI, Tuple SI, List SI;

tt: Tuple SI == (1,2,3,4);
tl: List SI == [tt];

print("tt = ")(tl)();

print("first(tt) = ")(first(tt))();

print("rest(tt) = ")([rest(tt)]@List SI)();