diff options
| -rw-r--r-- | backends/IsabelleHOL/Primitives.thy | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/backends/IsabelleHOL/Primitives.thy b/backends/IsabelleHOL/Primitives.thy index a0cc40bd..22377315 100644 --- a/backends/IsabelleHOL/Primitives.thy +++ b/backends/IsabelleHOL/Primitives.thy @@ -3,11 +3,17 @@ theory Primitives imports "HOL-Library.Monad_Syntax" begin +typedef u32 = "{n. (n :: nat) \<le> 4294967295}" + morphisms Rep_u32 Abs_u32 +proof + show "0 \<in> {n. (n :: nat) \<le> 4294967295}" by simp +qed + +definition u32_lt :: "u32 \<Rightarrow> u32 \<Rightarrow> bool" where + "u32_lt a b \<equiv> Rep_u32 a < Rep_u32 b" + -datatype u32 = u32 nat datatype 'a result = Ok 'a | Err -fun u32_lt :: "u32 \<Rightarrow> u32 \<Rightarrow> bool" where - "u32_lt (u32 a) (u32 b) = (a < b)" definition bind :: "'a result \<Rightarrow> ('a \<Rightarrow> 'b result) \<Rightarrow> 'b result" where "bind m f \<equiv> (case m of Err \<Rightarrow> Err | Ok a \<Rightarrow> f a)" @@ -16,4 +22,6 @@ adhoc_overloading Monad_Syntax.bind bind declare bind_def[simp] +(* TODO: instantiation to make u32 usable with literal numbers etc. *) + end
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