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--* Subject: [4] internal compiler error (bad case 19) [bug.as][0.36.0]

--@ Fixed  by:  SSD   Fri Jul 15 11:53:58 EDT 1994 
--@ Tested by:  none 
--@ Summary:    inlExpr was inlining too much on the left-hand side of FOAM_Set expressions. 

------------------------------- reference.as ----------------------------------
--
-- vinci.inf.ethz.ch{bronstei} 91: asharp -Q2 -Fc reference.as
-- Bug: Bad case 19 (line 2339 in file ../src/genc.c).
--
-- Works ok with -Q1

#include "aslib.as"

Reference(T:Type): BasicType with {
	apply: % -> T;
	nil: %;
	nil?: % -> Boolean;
	ref: T -> %;
	set!: (%, T) -> T
} == add {
	macro Rep == P;
	macro R == Record(val:T);

	-- untagged union of Record and Nil
	P: with {
		nil?:    % -> Boolean;
		nilptr:  %;
		recptr:  R -> %;
		value:   % -> R;
		=:       (%, %) -> Boolean;
	} == add {
		macro Rep == Pointer;
		import from {Rep, Pointer};
		nil?(p: %):Boolean	== nil? rep p;
		nilptr:%		== per(nil$Pointer);
		recptr(r:R):%		== r pretend %;
		value(p:%):R		== p pretend R;
		(p:%) = (q:%):Boolean	== rep p = rep q;
	}
	import from {R, Rep};

	sample:%			== nil;
	(p:%) = (q:%):Boolean		== rep p = rep q;
	nil:%				== per nilptr;
	nil?(p:%):Boolean		== nil? rep p;
	ref(x:T):%			== per recptr [x];
	apply(p:%):T			== value(rep p).val;
	set!(p:%, x:T):T		== value(rep p).val := x;

	(p:TextWriter) << (q:%):TextWriter == {
		nil? q => p << "NIL";
		p << "ref(*)";
	}
}