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theory Primitives imports
Main
"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 'a result = Ok 'a | Err
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)"
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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