--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOL/Word/Bits.thy Mon Dec 23 18:37:51 2013 +0100
@@ -0,0 +1,39 @@
+(* Title: HOL/Word/Bit_Operations.thy
+ Author: Author: Brian Huffman, PSU and Gerwin Klein, NICTA
+*)
+
+header {* Syntactic classes for bitwise operations *}
+
+theory Bits
+imports Main
+begin
+
+class bit =
+ fixes bitNOT :: "'a \<Rightarrow> 'a" ("NOT _" [70] 71)
+ and bitAND :: "'a \<Rightarrow> 'a \<Rightarrow> 'a" (infixr "AND" 64)
+ and bitOR :: "'a \<Rightarrow> 'a \<Rightarrow> 'a" (infixr "OR" 59)
+ and bitXOR :: "'a \<Rightarrow> 'a \<Rightarrow> 'a" (infixr "XOR" 59)
+
+text {*
+ We want the bitwise operations to bind slightly weaker
+ than @{text "+"} and @{text "-"}, but @{text "~~"} to
+ bind slightly stronger than @{text "*"}.
+*}
+
+text {*
+ Testing and shifting operations.
+*}
+
+class bits = bit +
+ fixes test_bit :: "'a \<Rightarrow> nat \<Rightarrow> bool" (infixl "!!" 100)
+ and lsb :: "'a \<Rightarrow> bool"
+ and set_bit :: "'a \<Rightarrow> nat \<Rightarrow> bool \<Rightarrow> 'a"
+ and set_bits :: "(nat \<Rightarrow> bool) \<Rightarrow> 'a" (binder "BITS " 10)
+ and shiftl :: "'a \<Rightarrow> nat \<Rightarrow> 'a" (infixl "<<" 55)
+ and shiftr :: "'a \<Rightarrow> nat \<Rightarrow> 'a" (infixl ">>" 55)
+
+class bitss = bits +
+ fixes msb :: "'a \<Rightarrow> bool"
+
+end
+