Added various MACRO-10 expression improvements

apps/pdp10/tests/MACTEST.MAC.txt

@@ -0,0 +1,27 @@
+	TITLE 	STORE TEXT CHARACTER BY CHARACTER
+	SUBTTL	%1 5-APR-72
+
+	DEFINE TEXT (C)<
+	N==0				;;INITIAL CONDITION
+	IRPC C,<N==N+1>			;;COUNT CHARACTERS
+	CODE (N,C)			;;CALL MACRO TO STORE TEXT
+	>				;END OF TEXT MACRO
+
+	DEFINE CODE (N,C)<
+	ZZ==N				;;INITIAL CONDITION
+	IRPC C,<
+	IFN ZZ&777B8,<
+		EXP ZZ			;;WORD FULL
+		ZZ==0>			;;START AGAIN WITH 0
+	ZZ=ZZ+9+"C">			;;END OF IRPC
+	IFN ZZ,<DEFINE SHIFT		;;REMAINDER LEFT
+	 IFE ZZ&777B8,>			;;IF NOT LEFT JUSTIFIED
+	 ZZ=ZZ+9			;;MOVE LEFT 9 BITS
+	SHIFT>				;;RECURSE
+	>				;;END OF DEFINE
+	SHIFT				;;START MOVING LEFT
+	EXP ZZ>				;;END OF IFN ZZ
+	>				;END OF CODE MACRO
+
+	TEXT (ABCDEFGHIJKL)
+	END