blob: d9e5ca4d345f427e082b9cf9c1d8f5770d7b8bb6 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
|
(*
Example proof document for Isabelle/Isar Proof General,
using symbols.
View and process this document with Unicode Tokens engaged.
$Id$
*)
theory "Example-Xsym" imports Main begin
text {* Proper proof text -- \<^bitalic>naive version\<^eitalic>. *}
theorem and_comms: "\<phi> \<and> \<psi> \<longrightarrow> \<psi> \<and> \<phi>"
proof
assume "\<phi> \<and> \<psi>"
then show "\<psi> \<and> \<phi>"
proof
assume \<psi> and \<phi>
then show ?thesis ..
qed
qed
text {* \<^bbold>Unstructured\<^ebold> proof script. *}
theorem "\<phi>\<^isub>\<alpha> \<and> \<phi>\<^isub>\<beta> \<longrightarrow> \<phi>\<^isub>\<beta> \<and> \<phi>\<^isub>\<alpha>"
apply (rule impI)
apply (erule conjE)
apply (rule conjI)
apply assumption
apply assumption
done
end
|