src/HOL/Filter.thy
changeset 62102 877463945ce9
parent 62101 26c0a70f78a3
child 62123 df65f5c27c15
equal deleted inserted replaced
62101:26c0a70f78a3 62102:877463945ce9
    23 
    23 
    24 typedef 'a filter = "{F :: ('a \<Rightarrow> bool) \<Rightarrow> bool. is_filter F}"
    24 typedef 'a filter = "{F :: ('a \<Rightarrow> bool) \<Rightarrow> bool. is_filter F}"
    25 proof
    25 proof
    26   show "(\<lambda>x. True) \<in> ?filter" by (auto intro: is_filter.intro)
    26   show "(\<lambda>x. True) \<in> ?filter" by (auto intro: is_filter.intro)
    27 qed
    27 qed
       
    28 
       
    29 text \<open>Kill code generation for filters\<close>
       
    30 
       
    31 code_datatype Abs_filter
       
    32 declare [[code abort: Rep_filter]]
    28 
    33 
    29 lemma is_filter_Rep_filter: "is_filter (Rep_filter F)"
    34 lemma is_filter_Rep_filter: "is_filter (Rep_filter F)"
    30   using Rep_filter [of F] by simp
    35   using Rep_filter [of F] by simp
    31 
    36 
    32 lemma Abs_filter_inverse':
    37 lemma Abs_filter_inverse':