--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/doc-src/Intro/gate.thy Wed Nov 10 05:06:55 1993 +0100
@@ -0,0 +1,5 @@
+Gate = FOL +
+consts nand,xor :: "[o,o] => o"
+rules nand_def "nand(P,Q) == ~(P & Q)"
+ xor_def "xor(P,Q) == P & ~Q | ~P & Q"
+end