From: matitaweb Date: Mon, 7 Nov 2011 14:43:20 +0000 (+0000) Subject: commit by user andrea X-Git-Tag: make_still_working~2130 X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=commitdiff_plain;h=80e732607c2b96569ed7826bb2372bc8ace885db;p=helm.git commit by user andrea --- diff --git a/weblib/tutorial/chapter4.ma b/weblib/tutorial/chapter4.ma index bb01c3e8b..9bfb3891c 100644 --- a/weblib/tutorial/chapter4.ma +++ b/weblib/tutorial/chapter4.ma @@ -1,8 +1,13 @@ +include "tutorial/chapter3.ma". -include "arithmetics/nat.ma". -include "basics/list.ma". +(* As a simple application of lists, let us now consider strings of characters +over a given alphabet Alpha. We shall assume to have a decidable equality between +characters, that is a (computable) function eqb associating a boolean value true +or false to each pair of characters; eqb is correct, in the sense that (eqb x y) +if and only if (x = y). The type Alpha of alphabets is hence defined by the +following record *) -interpretation "iff" 'iff a b = (iff a b). +interpretation "iff" 'iff a b = (iff a b). record Alpha : Type[1] ≝ { carr :> Type[0]; eqb: carr → carr → a href="cic:/matita/basics/bool/bool.ind(1,0,0)"bool/a; @@ -12,73 +17,81 @@ record Alpha : Type[1] ≝ { carr :> Type[0]; notation "a == b" non associative with precedence 45 for @{ 'eqb $a $b }. interpretation "eqb" 'eqb a b = (eqb ? a b). -definition word ≝ λS:a href="cic:/matita/tutorial/re/Alpha.ind(1,0,0)"Alpha/a.a href="cic:/matita/basics/list/list.ind(1,0,1)"list/a S. +definition word ≝ λS: a href="cic:/matita/tutorial/chapter4/Alpha.ind(1,0,0)"Alpha/a.a href="cic:/matita/tutorial/chapter3/list.ind(1,0,1)"list/a S. -inductive re (S: a href="cic:/matita/tutorial/re/Alpha.ind(1,0,0)"Alpha/a) : Type[0] ≝ - z: re S - | e: re S - | s: S → re S - | c: re S → re S → re S - | o: re S → re S → re S - | k: re S → re S. +inductive re (S: a href="cic:/matita/tutorial/chapter4/Alpha.ind(1,0,0)"Alpha/a) : Type[0] ≝ + zero: re S + | epsilon: re S + | char: S → re S + | concat: re S → re S → re S + | or: re S → re S → re S + | star: re S → re S. -notation < "a \sup ⋇" non associative with precedence 90 for @{ 'pk $a}. -notation > "a ^ *" non associative with precedence 90 for @{ 'pk $a}. -interpretation "star" 'pk a = (k ? a). -interpretation "or" 'plus a b = (o ? a b). +(* notation < "a \sup ⋇" non associative with precedence 90 for @{ 'pk $a}. *) +notation "a ^ *" non associative with precedence 90 for @{ 'kstar $a}. +interpretation "star" 'kstar a = (star ? a). +interpretation "or" 'plus a b = (or ? a b). -notation "a · b" non associative with precedence 60 for @{ 'pc $a $b}. -interpretation "cat" 'pc a b = (c ? a b). +notation "a · b" non associative with precedence 60 for @{ 'concat $a $b}. +interpretation "cat" 'concat a b = (concat ? a b). (* to get rid of \middot coercion c : ∀S:Alpha.∀p:re S. re S → re S ≝ c on _p : re ? to ∀_:?.?. *) -notation < "a" non associative with precedence 90 for @{ 'ps $a}. -notation > "` term 90 a" non associative with precedence 90 for @{ 'ps $a}. -interpretation "atom" 'ps a = (s ? a). +(* notation < "a" non associative with precedence 90 for @{ 'ps $a}. *) +notation "` term 90 a" non associative with precedence 90 for @{ 'atom $a}. +interpretation "atom" 'atom a = (char ? a). notation "ϵ" non associative with precedence 90 for @{ 'epsilon }. -interpretation "epsilon" 'epsilon = (e ?). +interpretation "epsilon" 'epsilon = (epsilon ?). notation "∅" non associative with precedence 90 for @{ 'empty }. -interpretation "empty" 'empty = (z ?). +interpretation "empty" 'empty = (zero ?). -let rec flatten (S : a href="cic:/matita/tutorial/re/Alpha.ind(1,0,0)"Alpha/a) (l : a href="cic:/matita/basics/list/list.ind(1,0,1)"list/a (a href="cic:/matita/tutorial/re/word.def(3)"word/a S)) on l : a href="cic:/matita/tutorial/re/word.def(3)"word/a S ≝ +let rec flatten (S : a href="cic:/matita/tutorial/chapter4/Alpha.ind(1,0,0)"Alpha/a) (l : a href="cic:/matita/tutorial/chapter3/list.ind(1,0,1)"list/a (a href="cic:/matita/tutorial/chapter4/word.def(3)"word/a S)) on l : a href="cic:/matita/tutorial/chapter4/word.def(3)"word/a S ≝ match l with [ nil ⇒ a title="nil" href="cic:/fakeuri.def(1)"[/a ] | cons w tl ⇒ w a title="append" href="cic:/fakeuri.def(1)"@/a flatten ? tl ]. -let rec conjunct (S : a href="cic:/matita/tutorial/re/Alpha.ind(1,0,0)"Alpha/a) (l : a href="cic:/matita/basics/list/list.ind(1,0,1)"list/a (a href="cic:/matita/tutorial/re/word.def(3)"word/a S)) (r : a href="cic:/matita/tutorial/re/word.def(3)"word/a S → Prop) on l: Prop ≝ -match l with [ nil ⇒ a href="cic:/matita/basics/logic/True.ind(1,0,0)"True/a | cons w tl ⇒ r w a title="logical and" href="cic:/fakeuri.def(1)"∧/a conjunct ? tl r ]. +let rec conjunct (S : a href="cic:/matita/tutorial/chapter4/Alpha.ind(1,0,0)"Alpha/a) (l : a href="cic:/matita/tutorial/chapter3/list.ind(1,0,1)"list/a (a href="cic:/matita/tutorial/chapter4/word.def(3)"word/a S)) (L :a href="cic:/matita/tutorial/chapter4/word.def(3)"word/a S → Prop) on l: Prop ≝ +match l with [ nil ⇒ a href="cic:/matita/basics/logic/True.ind(1,0,0)"True/a | cons w tl ⇒ L w a title="logical and" href="cic:/fakeuri.def(1)"∧/a conjunct ? tl L ]. -definition empty_lang ≝ λS.λw:a href="cic:/matita/tutorial/re/word.def(3)"word/a S.a href="cic:/matita/basics/logic/False.ind(1,0,0)"False/a. -notation "{}" non associative with precedence 90 for @{'empty_lang}. -interpretation "empty lang" 'empty_lang = (empty_lang ?). +definition empty_lang ≝ λS.λw:a href="cic:/matita/tutorial/chapter4/word.def(3)"word/a S.a href="cic:/matita/basics/logic/False.ind(1,0,0)"False/a. +(* notation "{}" non associative with precedence 90 for @{'empty_lang}. *) +interpretation "empty lang" 'empty = (empty_lang ?). -definition sing_lang ≝ λS.λx,w:a href="cic:/matita/tutorial/re/word.def(3)"word/a S.xa title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/aw. -notation "{x}" non associative with precedence 90 for @{'sing_lang $x}. +definition sing_lang ≝ λS.λx,w:a href="cic:/matita/tutorial/chapter4/word.def(3)"word/a S.x a title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/a w. +notation "{: x }" non associative with precedence 90 for @{'sing_lang $x}. interpretation "sing lang" 'sing_lang x = (sing_lang ? x). -definition union : ∀S,l1,l2,w.Prop ≝ λS.λl1,l2.λw:a href="cic:/matita/tutorial/re/word.def(3)"word/a S.l1 w a title="logical or" href="cic:/fakeuri.def(1)"∨/a l2 w. +definition union : ∀S,L1,L2,w.Prop ≝ λS,L1,L2.λw: a href="cic:/matita/tutorial/chapter4/word.def(3)"word/a S.L1 w a title="logical or" href="cic:/fakeuri.def(1)"∨/a L2 w. interpretation "union lang" 'union a b = (union ? a b). definition cat : ∀S,l1,l2,w.Prop ≝ - λS.λl1,l2.λw:a href="cic:/matita/tutorial/re/word.def(3)"word/a S.a title="exists" href="cic:/fakeuri.def(1)"∃/aw1,w2.w1 a title="append" href="cic:/fakeuri.def(1)"@/a w2 a title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/a w a title="logical and" href="cic:/fakeuri.def(1)"∧/a l1 w1 a title="logical and" href="cic:/fakeuri.def(1)"∧/a l2 w2. + λS.λl1,l2.λw:a href="cic:/matita/tutorial/chapter4/word.def(3)"word/a S.a title="exists" href="cic:/fakeuri.def(1)"∃/aw1,w2.w1 a title="append" href="cic:/fakeuri.def(1)"@/a w2 a title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/a w a title="logical and" href="cic:/fakeuri.def(1)"∧/a l1 w1 a title="logical and" href="cic:/fakeuri.def(1)"∧/a l2 w2. interpretation "cat lang" 'pc a b = (cat ? a b). -definition star ≝ λS.λl.λw:a href="cic:/matita/tutorial/re/word.def(3)"word/a S.a title="exists" href="cic:/fakeuri.def(1)"∃/alw.a href="cic:/matita/tutorial/re/flatten.fix(0,1,4)"flatten/a ? lw a title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/a w a title="logical and" href="cic:/fakeuri.def(1)"∧/a a href="cic:/matita/tutorial/re/conjunct.fix(0,1,4)"conjunct/a ? lw l. -interpretation "star lang" 'pk l = (star ? l). +definition star ≝ λS.λl.λw:a href="cic:/matita/tutorial/chapter4/word.def(3)"word/a S.a title="exists" href="cic:/fakeuri.def(1)"∃/alw. a href="cic:/matita/tutorial/chapter4/flatten.fix(0,1,4)"flatten/a ? lw a title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/a w a title="logical and" href="cic:/fakeuri.def(1)"∧/a a href="cic:/matita/tutorial/chapter4/conjunct.fix(0,1,4)"conjunct/a ? lw l. +interpretation "star lang" 'kstar l = (star ? l). notation > "𝐋 term 70 E" non associative with precedence 75 for @{in_l ? $E}. -let rec in_l (S : Alpha) (r : re S) on r : word S → Prop ≝ +let rec in_l (S : a href="cic:/matita/tutorial/chapter4/Alpha.ind(1,0,0)"Alpha/a) (r : a href="cic:/matita/tutorial/chapter4/re.ind(1,0,1)"re/a S) on r : a href="cic:/matita/tutorial/chapter4/word.def(3)"word/a S → Prop ≝ match r with -[ z ⇒ {} -| e ⇒ { [ ] } -| s x ⇒ { [x] } -| c r1 r2 ⇒ 𝐋 r1 · 𝐋 r2 -| o r1 r2 ⇒ 𝐋 r1 ∪ 𝐋 r2 -| k r1 ⇒ (𝐋 r1) ^*]. + [ zero ⇒ a title="empty lang" href="cic:/fakeuri.def(1)"∅/a + | epsilon ⇒ a title="sing lang" href="cic:/fakeuri.def(1)"{/a: a title="nil" href="cic:/fakeuri.def(1)"[/a] } + | char x ⇒ a title="sing lang" href="cic:/fakeuri.def(1)"{/a: a title="cons" href="cic:/fakeuri.def(1)"[/ax]span style="text-decoration: underline;"/span} + | _ ⇒ a title="empty lang" href="cic:/fakeuri.def(1)"∅/a + ]. + + +(* + | concat r1 r2 ⇒ 𝐋 r1 · 𝐋 r2 + | or r1 r2 ⇒ 𝐋 r1 ∪ 𝐋 r2 + | star r1 ⇒ (𝐋 r1) ^* + ]. + +*) -notation "𝐋 term 70 E" non associative with precedence 75 for @{'in_l $E}. + notation "𝐋 term 70 E" non associative with precedence 75 for @{'in_l $E}. interpretation "in_l" 'in_l E = (in_l ? E). interpretation "in_l mem" 'mem w l = (in_l ? l w). @@ -126,620 +139,4 @@ nlet rec forget (S: Alpha) (l : pitem S) on l: re S ≝ notation < "|term 19 e|" non associative with precedence 70 for @{'forget $e}. interpretation "forget" 'forget a = (forget ? a). -notation "\fst term 90 x" non associative with precedence 90 for @{'fst $x}. -interpretation "fst" 'fst x = (fst ? ? x). -notation > "\snd term 90 x" non associative with precedence 90 for @{'snd $x}. -interpretation "snd" 'snd x = (snd ? ? x). - -notation > "𝐋\p\ term 70 E" non associative with precedence 75 for @{in_pl ? $E}. -nlet rec in_pl (S : Alpha) (r : pitem S) on r : word S → Prop ≝ -match r with -[ pz ⇒ {} -| pe ⇒ {} -| ps _ ⇒ {} -| pp x ⇒ { [x] } -| pc r1 r2 ⇒ 𝐋\p\ r1 · 𝐋 |r2| ∪ 𝐋\p\ r2 -| po r1 r2 ⇒ 𝐋\p\ r1 ∪ 𝐋\p\ r2 -| pk r1 ⇒ 𝐋\p\ r1 · 𝐋 (|r1|^* ) ]. -notation > "𝐋\p term 70 E" non associative with precedence 75 for @{'in_pl $E}. -notation "𝐋\sub(\p) term 70 E" non associative with precedence 75 for @{'in_pl $E}. -interpretation "in_pl" 'in_pl E = (in_pl ? E). -interpretation "in_pl mem" 'mem w l = (in_pl ? l w). - -ndefinition epsilon ≝ λS,b.if b then { ([ ] : word S) } else {}. - -interpretation "epsilon" 'epsilon = (epsilon ?). -notation < "ϵ b" non associative with precedence 90 for @{'app_epsilon $b}. -interpretation "epsilon lang" 'app_epsilon b = (epsilon ? b). - -ndefinition in_prl ≝ λS : Alpha.λp:pre S. 𝐋\p (\fst p) ∪ ϵ (\snd p). - -interpretation "in_prl mem" 'mem w l = (in_prl ? l w). -interpretation "in_prl" 'in_pl E = (in_prl ? E). - -nlemma append_eq_nil : ∀S.∀w1,w2:word S. w1 @ w2 = [ ] → w1 = [ ]. -#S w1; nelim w1; //. #x tl IH w2; nnormalize; #abs; ndestruct; nqed. - -(* lemma 12 *) -nlemma epsilon_in_true : ∀S.∀e:pre S. [ ] ∈ e ↔ \snd e = true. -#S r; ncases r; #e b; @; ##[##2: #H; nrewrite > H; @2; /2/; ##] ncases b;//; -nnormalize; *; ##[##2:*] nelim e; -##[ ##1,2: *; ##| #c; *; ##| #c; nnormalize; #; ndestruct; ##| ##7: #p H; -##| #r1 r2 H G; *; ##[##2: /3/ by or_intror] -##| #r1 r2 H1 H2; *; /3/ by or_intror, or_introl; ##] -*; #w1; *; #w2; *; *; #defw1; nrewrite > (append_eq_nil … w1 w2 …); /3/ by {};//; -nqed. - -nlemma not_epsilon_lp : ∀S:Alpha.∀e:pitem S. ¬ ((𝐋\p e) [ ]). -#S e; nelim e; nnormalize; /2/ by nmk; -##[ #; @; #; ndestruct; -##| #r1 r2 n1 n2; @; *; /2/; *; #w1; *; #w2; *; *; #H; - nrewrite > (append_eq_nil …H…); /2/; -##| #r1 r2 n1 n2; @; *; /2/; -##| #r n; @; *; #w1; *; #w2; *; *; #H; - nrewrite > (append_eq_nil …H…); /2/;##] -nqed. - -ndefinition lo ≝ λS:Alpha.λa,b:pre S.〈\fst a + \fst b,\snd a || \snd b〉. -notation "a ⊕ b" left associative with precedence 60 for @{'oplus $a $b}. -interpretation "oplus" 'oplus a b = (lo ? a b). - -ndefinition lc ≝ λS:Alpha.λbcast:∀S:Alpha.∀E:pitem S.pre S.λa,b:pre S. - match a with [ mk_pair e1 b1 ⇒ - match b1 with - [ false ⇒ 〈e1 · \fst b, \snd b〉 - | true ⇒ 〈e1 · \fst (bcast ? (\fst b)),\snd b || \snd (bcast ? (\fst b))〉]]. - -notation < "a ⊙ b" left associative with precedence 60 for @{'lc $op $a $b}. -interpretation "lc" 'lc op a b = (lc ? op a b). -notation > "a ⊙ b" left associative with precedence 60 for @{'lc eclose $a $b}. - -ndefinition lk ≝ λS:Alpha.λbcast:∀S:Alpha.∀E:pitem S.pre S.λa:pre S. - match a with [ mk_pair e1 b1 ⇒ - match b1 with - [ false ⇒ 〈e1^*, false〉 - | true ⇒ 〈(\fst (bcast ? e1))^*, true〉]]. - -notation < "a \sup ⊛" non associative with precedence 90 for @{'lk $op $a}. -interpretation "lk" 'lk op a = (lk ? op a). -notation > "a^⊛" non associative with precedence 90 for @{'lk eclose $a}. - -notation > "•" non associative with precedence 60 for @{eclose ?}. -nlet rec eclose (S: Alpha) (E: pitem S) on E : pre S ≝ - match E with - [ pz ⇒ 〈 ∅, false 〉 - | pe ⇒ 〈 ϵ, true 〉 - | ps x ⇒ 〈 `.x, false 〉 - | pp x ⇒ 〈 `.x, false 〉 - | po E1 E2 ⇒ •E1 ⊕ •E2 - | pc E1 E2 ⇒ •E1 ⊙ 〈 E2, false 〉 - | pk E ⇒ 〈(\fst (•E))^*,true〉]. -notation < "• x" non associative with precedence 60 for @{'eclose $x}. -interpretation "eclose" 'eclose x = (eclose ? x). -notation > "• x" non associative with precedence 60 for @{'eclose $x}. - -ndefinition reclose ≝ λS:Alpha.λp:pre S.let p' ≝ •\fst p in 〈\fst p',\snd p || \snd p'〉. -interpretation "reclose" 'eclose x = (reclose ? x). - -ndefinition eq_f1 ≝ λS.λa,b:word S → Prop.∀w.a w ↔ b w. -notation > "A =1 B" non associative with precedence 45 for @{'eq_f1 $A $B}. -notation "A =\sub 1 B" non associative with precedence 45 for @{'eq_f1 $A $B}. -interpretation "eq f1" 'eq_f1 a b = (eq_f1 ? a b). - -naxiom extP : ∀S.∀p,q:word S → Prop.(p =1 q) → p = q. - -nlemma epsilon_or : ∀S:Alpha.∀b1,b2. ϵ(b1 || b2) = ϵ b1 ∪ ϵ b2. ##[##2: napply S] -#S b1 b2; ncases b1; ncases b2; napply extP; #w; nnormalize; @; /2/; *; //; *; -nqed. - -nlemma cupA : ∀S.∀a,b,c:word S → Prop.a ∪ b ∪ c = a ∪ (b ∪ c). -#S a b c; napply extP; #w; nnormalize; @; *; /3/; *; /3/; nqed. - -nlemma cupC : ∀S. ∀a,b:word S → Prop.a ∪ b = b ∪ a. -#S a b; napply extP; #w; @; *; nnormalize; /2/; nqed. - -(* theorem 16: 2 *) -nlemma oplus_cup : ∀S:Alpha.∀e1,e2:pre S.𝐋\p (e1 ⊕ e2) = 𝐋\p e1 ∪ 𝐋\p e2. -#S r1; ncases r1; #e1 b1 r2; ncases r2; #e2 b2; -nwhd in ⊢ (??(??%)?); -nchange in ⊢(??%?) with (𝐋\p (e1 + e2) ∪ ϵ (b1 || b2)); -nchange in ⊢(??(??%?)?) with (𝐋\p (e1) ∪ 𝐋\p (e2)); -nrewrite > (epsilon_or S …); nrewrite > (cupA S (𝐋\p e1) …); -nrewrite > (cupC ? (ϵ b1) …); nrewrite < (cupA S (𝐋\p e2) …); -nrewrite > (cupC ? ? (ϵ b1) …); nrewrite < (cupA …); //; -nqed. - -nlemma odotEt : - ∀S.∀e1,e2:pitem S.∀b2. 〈e1,true〉 ⊙ 〈e2,b2〉 = 〈e1 · \fst (•e2),b2 || \snd (•e2)〉. -#S e1 e2 b2; nnormalize; ncases (•e2); //; nqed. - -nlemma LcatE : ∀S.∀e1,e2:pitem S.𝐋\p (e1 · e2) = 𝐋\p e1 · 𝐋 |e2| ∪ 𝐋\p e2. //; nqed. - -nlemma cup_dotD : ∀S.∀p,q,r:word S → Prop.(p ∪ q) · r = (p · r) ∪ (q · r). -#S p q r; napply extP; #w; nnormalize; @; -##[ *; #x; *; #y; *; *; #defw; *; /7/ by or_introl, or_intror, ex_intro, conj; -##| *; *; #x; *; #y; *; *; /7/ by or_introl, or_intror, ex_intro, conj; ##] -nqed. - -nlemma cup0 :∀S.∀p:word S → Prop.p ∪ {} = p. -#S p; napply extP; #w; nnormalize; @; /2/; *; //; *; nqed. - -nlemma erase_dot : ∀S.∀e1,e2:pitem S.𝐋 |e1 · e2| = 𝐋 |e1| · 𝐋 |e2|. -#S e1 e2; napply extP; nnormalize; #w; @; *; #w1; *; #w2; *; *; /7/ by ex_intro, conj; -nqed. - -nlemma erase_plus : ∀S.∀e1,e2:pitem S.𝐋 |e1 + e2| = 𝐋 |e1| ∪ 𝐋 |e2|. -#S e1 e2; napply extP; nnormalize; #w; @; *; /4/ by or_introl, or_intror; nqed. - -nlemma erase_star : ∀S.∀e1:pitem S.𝐋 |e1|^* = 𝐋 |e1^*|. //; nqed. - -ndefinition substract := λS.λp,q:word S → Prop.λw.p w ∧ ¬ q w. -interpretation "substract" 'minus a b = (substract ? a b). - -nlemma cup_sub: ∀S.∀a,b:word S → Prop. ¬ (a []) → a ∪ (b - {[]}) = (a ∪ b) - {[]}. -#S a b c; napply extP; #w; nnormalize; @; *; /4/; *; /4/; nqed. - -nlemma sub0 : ∀S.∀a:word S → Prop. a - {} = a. -#S a; napply extP; #w; nnormalize; @; /3/; *; //; nqed. - -nlemma subK : ∀S.∀a:word S → Prop. a - a = {}. -#S a; napply extP; #w; nnormalize; @; *; /2/; nqed. - -nlemma subW : ∀S.∀a,b:word S → Prop.∀w.(a - b) w → a w. -#S a b w; nnormalize; *; //; nqed. - -nlemma erase_bull : ∀S.∀a:pitem S. |\fst (•a)| = |a|. -#S a; nelim a; // by {}; -##[ #e1 e2 IH1 IH2; nchange in ⊢ (???%) with (|e1| · |e2|); - nrewrite < IH1; nrewrite < IH2; - nchange in ⊢ (??(??%)?) with (\fst (•e1 ⊙ 〈e2,false〉)); - ncases (•e1); #e3 b; ncases b; nnormalize; - ##[ ncases (•e2); //; ##| nrewrite > IH2; //] -##| #e1 e2 IH1 IH2; nchange in ⊢ (???%) with (|e1| + |e2|); - nrewrite < IH2; nrewrite < IH1; - nchange in ⊢ (??(??%)?) with (\fst (•e1 ⊕ •e2)); - ncases (•e1); ncases (•e2); //; -##| #e IH; nchange in ⊢ (???%) with (|e|^* ); nrewrite < IH; - nchange in ⊢ (??(??%)?) with (\fst (•e))^*; //; ##] -nqed. - -nlemma eta_lp : ∀S.∀p:pre S.𝐋\p p = 𝐋\p 〈\fst p, \snd p〉. -#S p; ncases p; //; nqed. - -nlemma epsilon_dot: ∀S.∀p:word S → Prop. {[]} · p = p. -#S e; napply extP; #w; nnormalize; @; ##[##2: #Hw; @[]; @w; /3/; ##] -*; #w1; *; #w2; *; *; #defw defw1 Hw2; nrewrite < defw; nrewrite < defw1; -napply Hw2; nqed. - -(* theorem 16: 1 → 3 *) -nlemma odot_dot_aux : ∀S.∀e1,e2: pre S. - 𝐋\p (•(\fst e2)) = 𝐋\p (\fst e2) ∪ 𝐋 |\fst e2| → - 𝐋\p (e1 ⊙ e2) = 𝐋\p e1 · 𝐋 |\fst e2| ∪ 𝐋\p e2. -#S e1 e2 th1; ncases e1; #e1' b1'; ncases b1'; -##[ nwhd in ⊢ (??(??%)?); nletin e2' ≝ (\fst e2); nletin b2' ≝ (\snd e2); - nletin e2'' ≝ (\fst (•(\fst e2))); nletin b2'' ≝ (\snd (•(\fst e2))); - nchange in ⊢ (??%?) with (?∪?); - nchange in ⊢ (??(??%?)?) with (?∪?); - nchange in match (𝐋\p 〈?,?〉) with (?∪?); - nrewrite > (epsilon_or …); nrewrite > (cupC ? (ϵ ?)…); - nrewrite > (cupA …);nrewrite < (cupA ?? (ϵ?)…); - nrewrite > (?: 𝐋\p e2'' ∪ ϵ b2'' = 𝐋\p e2' ∪ 𝐋 |e2'|); ##[##2: - nchange with (𝐋\p 〈e2'',b2''〉 = 𝐋\p e2' ∪ 𝐋 |e2'|); - ngeneralize in match th1; - nrewrite > (eta_lp…); #th1; nrewrite > th1; //;##] - nrewrite > (eta_lp ? e2); - nchange in match (𝐋\p 〈\fst e2,?〉) with (𝐋\p e2'∪ ϵ b2'); - nrewrite > (cup_dotD …); nrewrite > (epsilon_dot…); - nrewrite > (cupC ? (𝐋\p e2')…); nrewrite > (cupA…);nrewrite > (cupA…); - nrewrite < (erase_bull S e2') in ⊢ (???(??%?)); //; -##| ncases e2; #e2' b2'; nchange in match (〈e1',false〉⊙?) with 〈?,?〉; - nchange in match (𝐋\p ?) with (?∪?); - nchange in match (𝐋\p (e1'·?)) with (?∪?); - nchange in match (𝐋\p 〈e1',?〉) with (?∪?); - nrewrite > (cup0…); - nrewrite > (cupA…); //;##] -nqed. - -nlemma sub_dot_star : - ∀S.∀X:word S → Prop.∀b. (X - ϵ b) · X^* ∪ {[]} = X^*. -#S X b; napply extP; #w; @; -##[ *; ##[##2: nnormalize; #defw; nrewrite < defw; @[]; @; //] - *; #w1; *; #w2; *; *; #defw sube; *; #lw; *; #flx cj; - @ (w1 :: lw); nrewrite < defw; nrewrite < flx; @; //; - @; //; napply (subW … sube); -##| *; #wl; *; #defw Pwl; nrewrite < defw; nelim wl in Pwl; ##[ #_; @2; //] - #w' wl' IH; *; #Pw' IHp; nlapply (IH IHp); *; - ##[ *; #w1; *; #w2; *; *; #defwl' H1 H2; - @; ncases b in H1; #H1; - ##[##2: nrewrite > (sub0…); @w'; @(w1@w2); - nrewrite > (associative_append ? w' w1 w2); - nrewrite > defwl'; @; ##[@;//] @(wl'); @; //; - ##| ncases w' in Pw'; - ##[ #ne; @w1; @w2; nrewrite > defwl'; @; //; @; //; - ##| #x xs Px; @(x::xs); @(w1@w2); - nrewrite > (defwl'); @; ##[@; //; @; //; @; nnormalize; #; ndestruct] - @wl'; @; //; ##] ##] - ##| #wlnil; nchange in match (flatten ? (w'::wl')) with (w' @ flatten ? wl'); - nrewrite < (wlnil); nrewrite > (append_nil…); ncases b; - ##[ ncases w' in Pw'; /2/; #x xs Pxs; @; @(x::xs); @([]); - nrewrite > (append_nil…); @; ##[ @; //;@; //; nnormalize; @; #; ndestruct] - @[]; @; //; - ##| @; @w'; @[]; nrewrite > (append_nil…); @; ##[##2: @[]; @; //] - @; //; @; //; @; *;##]##]##] -nqed. - -(* theorem 16: 1 *) -alias symbol "pc" (instance 13) = "cat lang". -alias symbol "in_pl" (instance 23) = "in_pl". -alias symbol "in_pl" (instance 5) = "in_pl". -alias symbol "eclose" (instance 21) = "eclose". -ntheorem bull_cup : ∀S:Alpha. ∀e:pitem S. 𝐋\p (•e) = 𝐋\p e ∪ 𝐋 |e|. -#S e; nelim e; //; - ##[ #a; napply extP; #w; nnormalize; @; *; /3/ by or_introl, or_intror; - ##| #a; napply extP; #w; nnormalize; @; *; /3/ by or_introl; *; - ##| #e1 e2 IH1 IH2; - nchange in ⊢ (??(??(%))?) with (•e1 ⊙ 〈e2,false〉); - nrewrite > (odot_dot_aux S (•e1) 〈e2,false〉 IH2); - nrewrite > (IH1 …); nrewrite > (cup_dotD …); - nrewrite > (cupA …); nrewrite > (cupC ?? (𝐋\p ?) …); - nchange in match (𝐋\p 〈?,?〉) with (𝐋\p e2 ∪ {}); nrewrite > (cup0 …); - nrewrite < (erase_dot …); nrewrite < (cupA …); //; - ##| #e1 e2 IH1 IH2; - nchange in match (•(?+?)) with (•e1 ⊕ •e2); nrewrite > (oplus_cup …); - nrewrite > (IH1 …); nrewrite > (IH2 …); nrewrite > (cupA …); - nrewrite > (cupC ? (𝐋\p e2)…);nrewrite < (cupA ??? (𝐋\p e2)…); - nrewrite > (cupC ?? (𝐋\p e2)…); nrewrite < (cupA …); - nrewrite < (erase_plus …); //. - ##| #e; nletin e' ≝ (\fst (•e)); nletin b' ≝ (\snd (•e)); #IH; - nchange in match (𝐋\p ?) with (𝐋\p 〈e'^*,true〉); - nchange in match (𝐋\p ?) with (𝐋\p (e'^* ) ∪ {[ ]}); - nchange in ⊢ (??(??%?)?) with (𝐋\p e' · 𝐋 |e'|^* ); - nrewrite > (erase_bull…e); - nrewrite > (erase_star …); - nrewrite > (?: 𝐋\p e' = 𝐋\p e ∪ (𝐋 |e| - ϵ b')); ##[##2: - nchange in IH : (??%?) with (𝐋\p e' ∪ ϵ b'); ncases b' in IH; - ##[ #IH; nrewrite > (cup_sub…); //; nrewrite < IH; - nrewrite < (cup_sub…); //; nrewrite > (subK…); nrewrite > (cup0…);//; - ##| nrewrite > (sub0 …); #IH; nrewrite < IH; nrewrite > (cup0 …);//; ##]##] - nrewrite > (cup_dotD…); nrewrite > (cupA…); - nrewrite > (?: ((?·?)∪{[]} = 𝐋 |e^*|)); //; - nchange in match (𝐋 |e^*|) with ((𝐋 |e|)^* ); napply sub_dot_star;##] - nqed. - -(* theorem 16: 3 *) -nlemma odot_dot: - ∀S.∀e1,e2: pre S. 𝐋\p (e1 ⊙ e2) = 𝐋\p e1 · 𝐋 |\fst e2| ∪ 𝐋\p e2. -#S e1 e2; napply odot_dot_aux; napply (bull_cup S (\fst e2)); nqed. - -nlemma dot_star_epsilon : ∀S.∀e:re S.𝐋 e · 𝐋 e^* ∪ {[]} = 𝐋 e^*. -#S e; napply extP; #w; nnormalize; @; -##[ *; ##[##2: #H; nrewrite < H; @[]; /3/] *; #w1; *; #w2; - *; *; #defw Hw1; *; #wl; *; #defw2 Hwl; @(w1 :: wl); - nrewrite < defw; nrewrite < defw2; @; //; @;//; -##| *; #wl; *; #defw Hwl; ncases wl in defw Hwl; ##[#defw; #; @2; nrewrite < defw; //] - #x xs defw; *; #Hx Hxs; @; @x; @(flatten ? xs); nrewrite < defw; - @; /2/; @xs; /2/;##] - nqed. - -nlemma nil_star : ∀S.∀e:re S. [ ] ∈ e^*. -#S e; @[]; /2/; nqed. - -nlemma cupID : ∀S.∀l:word S → Prop.l ∪ l = l. -#S l; napply extP; #w; @; ##[*]//; #; @; //; nqed. - -nlemma cup_star_nil : ∀S.∀l:word S → Prop. l^* ∪ {[]} = l^*. -#S a; napply extP; #w; @; ##[*; //; #H; nrewrite < H; @[]; @; //] #;@; //;nqed. - -nlemma rcanc_sing : ∀S.∀A,C:word S → Prop.∀b:word S . - ¬ (A b) → A ∪ { (b) } = C → A = C - { (b) }. -#S A C b nbA defC; nrewrite < defC; napply extP; #w; @; -##[ #Aw; /3/| *; *; //; #H nH; ncases nH; #abs; nlapply (abs H); *] -nqed. - -(* theorem 16: 4 *) -nlemma star_dot: ∀S.∀e:pre S. 𝐋\p (e^⊛) = 𝐋\p e · (𝐋 |\fst e|)^*. -#S p; ncases p; #e b; ncases b; -##[ nchange in match (〈e,true〉^⊛) with 〈?,?〉; - nletin e' ≝ (\fst (•e)); nletin b' ≝ (\snd (•e)); - nchange in ⊢ (??%?) with (?∪?); - nchange in ⊢ (??(??%?)?) with (𝐋\p e' · 𝐋 |e'|^* ); - nrewrite > (?: 𝐋\p e' = 𝐋\p e ∪ (𝐋 |e| - ϵ b' )); ##[##2: - nlapply (bull_cup ? e); #bc; - nchange in match (𝐋\p (•e)) in bc with (?∪?); - nchange in match b' in bc with b'; - ncases b' in bc; ##[##2: nrewrite > (cup0…); nrewrite > (sub0…); //] - nrewrite > (cup_sub…); ##[napply rcanc_sing] //;##] - nrewrite > (cup_dotD…); nrewrite > (cupA…);nrewrite > (erase_bull…); - nrewrite > (sub_dot_star…); - nchange in match (𝐋\p 〈?,?〉) with (?∪?); - nrewrite > (cup_dotD…); nrewrite > (epsilon_dot…); //; -##| nwhd in match (〈e,false〉^⊛); nchange in match (𝐋\p 〈?,?〉) with (?∪?); - nrewrite > (cup0…); - nchange in ⊢ (??%?) with (𝐋\p e · 𝐋 |e|^* ); - nrewrite < (cup0 ? (𝐋\p e)); //;##] -nqed. - -nlet rec pre_of_re (S : Alpha) (e : re S) on e : pitem S ≝ - match e with - [ z ⇒ pz ? - | e ⇒ pe ? - | s x ⇒ ps ? x - | c e1 e2 ⇒ pc ? (pre_of_re ? e1) (pre_of_re ? e2) - | o e1 e2 ⇒ po ? (pre_of_re ? e1) (pre_of_re ? e2) - | k e1 ⇒ pk ? (pre_of_re ? e1)]. - -nlemma notFalse : ¬False. @; //; nqed. - -nlemma dot0 : ∀S.∀A:word S → Prop. {} · A = {}. -#S A; nnormalize; napply extP; #w; @; ##[##2: *] -*; #w1; *; #w2; *; *; //; nqed. - -nlemma Lp_pre_of_re : ∀S.∀e:re S. 𝐋\p (pre_of_re ? e) = {}. -#S e; nelim e; ##[##1,2,3: //] -##[ #e1 e2 H1 H2; nchange in match (𝐋\p (pre_of_re S (e1 e2))) with (?∪?); - nrewrite > H1; nrewrite > H2; nrewrite > (dot0…); nrewrite > (cupID…);// -##| #e1 e2 H1 H2; nchange in match (𝐋\p (pre_of_re S (e1+e2))) with (?∪?); - nrewrite > H1; nrewrite > H2; nrewrite > (cupID…); // -##| #e1 H1; nchange in match (𝐋\p (pre_of_re S (e1^* ))) with (𝐋\p (pre_of_re ??) · ?); - nrewrite > H1; napply dot0; ##] -nqed. - -nlemma erase_pre_of_reK : ∀S.∀e. 𝐋 |pre_of_re S e| = 𝐋 e. -#S A; nelim A; //; -##[ #e1 e2 H1 H2; nchange in match (𝐋 (e1 · e2)) with (𝐋 e1·?); - nrewrite < H1; nrewrite < H2; // -##| #e1 e2 H1 H2; nchange in match (𝐋 (e1 + e2)) with (𝐋 e1 ∪ ?); - nrewrite < H1; nrewrite < H2; // -##| #e1 H1; nchange in match (𝐋 (e1^* )) with ((𝐋 e1)^* ); - nrewrite < H1; //] -nqed. - -(* corollary 17 *) -nlemma L_Lp_bull : ∀S.∀e:re S.𝐋 e = 𝐋\p (•pre_of_re ? e). -#S e; nrewrite > (bull_cup…); nrewrite > (Lp_pre_of_re…); -nrewrite > (cupC…); nrewrite > (cup0…); nrewrite > (erase_pre_of_reK…); //; -nqed. - -nlemma Pext : ∀S.∀f,g:word S → Prop. f = g → ∀w.f w → g w. -#S f g H; nrewrite > H; //; nqed. - -(* corollary 18 *) -ntheorem bull_true_epsilon : ∀S.∀e:pitem S. \snd (•e) = true ↔ [ ] ∈ |e|. -#S e; @; -##[ #defsnde; nlapply (bull_cup ? e); nchange in match (𝐋\p (•e)) with (?∪?); - nrewrite > defsnde; #H; - nlapply (Pext ??? H [ ] ?); ##[ @2; //] *; //; - -STOP - -notation > "\move term 90 x term 90 E" -non associative with precedence 60 for @{move ? $x $E}. -nlet rec move (S: Alpha) (x:S) (E: pitem S) on E : pre S ≝ - match E with - [ pz ⇒ 〈 ∅, false 〉 - | pe ⇒ 〈 ϵ, false 〉 - | ps y ⇒ 〈 `y, false 〉 - | pp y ⇒ 〈 `y, x == y 〉 - | po e1 e2 ⇒ \move x e1 ⊕ \move x e2 - | pc e1 e2 ⇒ \move x e1 ⊙ \move x e2 - | pk e ⇒ (\move x e)^⊛ ]. -notation < "\move\shy x\shy E" non associative with precedence 60 for @{'move $x $E}. -notation > "\move term 90 x term 90 E" non associative with precedence 60 for @{'move $x $E}. -interpretation "move" 'move x E = (move ? x E). - -ndefinition rmove ≝ λS:Alpha.λx:S.λe:pre S. \move x (\fst e). -interpretation "rmove" 'move x E = (rmove ? x E). - -nlemma XXz : ∀S:Alpha.∀w:word S. w ∈ ∅ → False. -#S w abs; ninversion abs; #; ndestruct; -nqed. - - -nlemma XXe : ∀S:Alpha.∀w:word S. w .∈ ϵ → False. -#S w abs; ninversion abs; #; ndestruct; -nqed. - -nlemma XXze : ∀S:Alpha.∀w:word S. w .∈ (∅ · ϵ) → False. -#S w abs; ninversion abs; #; ndestruct; /2/ by XXz,XXe; -nqed. - - -naxiom in_move_cat: - ∀S.∀w:word S.∀x.∀E1,E2:pitem S. w .∈ \move x (E1 · E2) → - (∃w1.∃w2. w = w1@w2 ∧ w1 .∈ \move x E1 ∧ w2 ∈ .|E2|) ∨ w .∈ \move x E2. -#S w x e1 e2 H; nchange in H with (w .∈ \move x e1 ⊙ \move x e2); -ncases e1 in H; ncases e2; -##[##1: *; ##[*; nnormalize; #; ndestruct] - #H; ninversion H; ##[##1,4,5,6: nnormalize; #; ndestruct] - nnormalize; #; ndestruct; ncases (?:False); /2/ by XXz,XXze; -##|##2: *; ##[*; nnormalize; #; ndestruct] - #H; ninversion H; ##[##1,4,5,6: nnormalize; #; ndestruct] - nnormalize; #; ndestruct; ncases (?:False); /2/ by XXz,XXze; -##| #r; *; ##[ *; nnormalize; #; ndestruct] - #H; ninversion H; ##[##1,4,5,6: nnormalize; #; ndestruct] - ##[##2: nnormalize; #; ndestruct; @2; @2; //.##] - nnormalize; #; ndestruct; ncases (?:False); /2/ by XXz; -##| #y; *; ##[ *; nnormalize; #defw defx; ndestruct; @2; @1; /2/ by conj;##] - #H; ninversion H; nnormalize; #; ndestruct; - ##[ncases (?:False); /2/ by XXz] /3/ by or_intror; -##| #r1 r2; *; ##[ *; #defw] - ... -nqed. - -ntheorem move_ok: - ∀S:Alpha.∀E:pre S.∀a,w.w .∈ \move a E ↔ (a :: w) .∈ E. -#S E; ncases E; #r b; nelim r; -##[##1,2: #a w; @; - ##[##1,3: nnormalize; *; ##[##1,3: *; #; ndestruct; ##| #abs; ncases (XXz … abs); ##] - #H; ninversion H; #; ndestruct; - ##|##*:nnormalize; *; ##[##1,3: *; #; ndestruct; ##| #H1; ncases (XXz … H1); ##] - #H; ninversion H; #; ndestruct;##] -##|#a c w; @; nnormalize; ##[*; ##[*; #; ndestruct; ##] #abs; ninversion abs; #; ndestruct;##] - *; ##[##2: #abs; ninversion abs; #; ndestruct; ##] *; #; ndestruct; -##|#a c w; @; nnormalize; - ##[ *; ##[ *; #defw; nrewrite > defw; #ca; @2; nrewrite > (eqb_t … ca); @; ##] - #H; ninversion H; #; ndestruct; - ##| *; ##[ *; #; ndestruct; ##] #H; ninversion H; ##[##2,3,4,5,6: #; ndestruct] - #d defw defa; ndestruct; @1; @; //; nrewrite > (eqb_true S d d); //. ##] -##|#r1 r2 H1 H2 a w; @; - ##[ #H; ncases (in_move_cat … H); - ##[ *; #w1; *; #w2; *; *; #defw w1m w2m; - ncases (H1 a w1); #H1w1; #_; nlapply (H1w1 w1m); #good; - nrewrite > defw; @2; @2 (a::w1); //; ncases good; ##[ *; #; ndestruct] //. - ##| - ... -##| -##| -##] -nqed. - - -notation > "x ↦* E" non associative with precedence 60 for @{move_star ? $x $E}. -nlet rec move_star (S : decidable) w E on w : bool × (pre S) ≝ - match w with - [ nil ⇒ E - | cons x w' ⇒ w' ↦* (x ↦ \snd E)]. - -ndefinition in_moves ≝ λS:decidable.λw.λE:bool × (pre S). \fst(w ↦* E). - -ncoinductive equiv (S:decidable) : bool × (pre S) → bool × (pre S) → Prop ≝ - mk_equiv: - ∀E1,E2: bool × (pre S). - \fst E1 = \fst E2 → - (∀x. equiv S (x ↦ \snd E1) (x ↦ \snd E2)) → - equiv S E1 E2. - -ndefinition NAT: decidable. - @ nat eqb; /2/. -nqed. - -include "hints_declaration.ma". - -alias symbol "hint_decl" (instance 1) = "hint_decl_Type1". -unification hint 0 ≔ ; X ≟ NAT ⊢ carr X ≡ nat. - -ninductive unit: Type[0] ≝ I: unit. - -nlet corec foo_nop (b: bool): - equiv ? - 〈 b, pc ? (ps ? 0) (pk ? (pc ? (ps ? 1) (ps ? 0))) 〉 - 〈 b, pc ? (pk ? (pc ? (ps ? 0) (ps ? 1))) (ps ? 0) 〉 ≝ ?. - @; //; #x; ncases x - [ nnormalize in ⊢ (??%%); napply (foo_nop false) - | #y; ncases y - [ nnormalize in ⊢ (??%%); napply (foo_nop false) - | #w; nnormalize in ⊢ (??%%); napply (foo_nop false) ]##] -nqed. - -(* -nlet corec foo (a: unit): - equiv NAT - (eclose NAT (pc ? (ps ? 0) (pk ? (pc ? (ps ? 1) (ps ? 0))))) - (eclose NAT (pc ? (pk ? (pc ? (ps ? 0) (ps ? 1))) (ps ? 0))) -≝ ?. - @; - ##[ nnormalize; // - ##| #x; ncases x - [ nnormalize in ⊢ (??%%); - nnormalize in foo: (? → ??%%); - @; //; #y; ncases y - [ nnormalize in ⊢ (??%%); napply foo_nop - | #y; ncases y - [ nnormalize in ⊢ (??%%); - - ##| #z; nnormalize in ⊢ (??%%); napply foo_nop ]##] - ##| #y; nnormalize in ⊢ (??%%); napply foo_nop - ##] -nqed. -*) - -ndefinition test1 : pre ? ≝ ❨ `0 | `1 ❩^* `0. -ndefinition test2 : pre ? ≝ ❨ (`0`1)^* `0 | (`0`1)^* `1 ❩. -ndefinition test3 : pre ? ≝ (`0 (`0`1)^* `1)^*. - - -nlemma foo: in_moves ? [0;0;1;0;1;1] (ɛ test3) = true. - nnormalize in match test3; - nnormalize; -//; -nqed. - -(**********************************************************) - -ninductive der (S: Type[0]) (a: S) : re S → re S → CProp[0] ≝ - der_z: der S a (z S) (z S) - | der_e: der S a (e S) (z S) - | der_s1: der S a (s S a) (e ?) - | der_s2: ∀b. a ≠ b → der S a (s S b) (z S) - | der_c1: ∀e1,e2,e1',e2'. in_l S [] e1 → der S a e1 e1' → der S a e2 e2' → - der S a (c ? e1 e2) (o ? (c ? e1' e2) e2') - | der_c2: ∀e1,e2,e1'. Not (in_l S [] e1) → der S a e1 e1' → - der S a (c ? e1 e2) (c ? e1' e2) - | der_o: ∀e1,e2,e1',e2'. der S a e1 e1' → der S a e2 e2' → - der S a (o ? e1 e2) (o ? e1' e2'). - -nlemma eq_rect_CProp0_r: - ∀A.∀a,x.∀p:eq ? x a.∀P: ∀x:A. eq ? x a → CProp[0]. P a (refl A a) → P x p. - #A; #a; #x; #p; ncases p; #P; #H; nassumption. -nqed. - -nlemma append1: ∀A.∀a:A.∀l. [a] @ l = a::l. //. nqed. - -naxiom in_l1: ∀S,r1,r2,w. in_l S [ ] r1 → in_l S w r2 → in_l S w (c S r1 r2). -(* #S; #r1; #r2; #w; nelim r1 - [ #K; ninversion K - | #H1; #H2; napply (in_c ? []); // - | (* tutti casi assurdi *) *) - -ninductive in_l' (S: Type[0]) : word S → re S → CProp[0] ≝ - in_l_empty1: ∀E.in_l S [] E → in_l' S [] E - | in_l_cons: ∀a,w,e,e'. in_l' S w e' → der S a e e' → in_l' S (a::w) e. - -ncoinductive eq_re (S: Type[0]) : re S → re S → CProp[0] ≝ - mk_eq_re: ∀E1,E2. - (in_l S [] E1 → in_l S [] E2) → - (in_l S [] E2 → in_l S [] E1) → - (∀a,E1',E2'. der S a E1 E1' → der S a E2 E2' → eq_re S E1' E2') → - eq_re S E1 E2. - -(* serve il lemma dopo? *) -ntheorem eq_re_is_eq: ∀S.∀E1,E2. eq_re S E1 E2 → ∀w. in_l ? w E1 → in_l ? w E2. - #S; #E1; #E2; #H1; #w; #H2; nelim H2 in E2 H1 ⊢ % - [ #r; #K (* ok *) - | #a; #w; #R1; #R2; #K1; #K2; #K3; #R3; #K4; @2 R2; //; ncases K4; - -(* IL VICEVERSA NON VALE *) -naxiom in_l_to_in_l: ∀S,w,E. in_l' S w E → in_l S w E. -(* #S; #w; #E; #H; nelim H - [ // - | #a; #w'; #r; #r'; #H1; (* e si cade qua sotto! *) - ] -nqed. *) - -ntheorem der1: ∀S,a,e,e',w. der S a e e' → in_l S w e' → in_l S (a::w) e. - #S; #a; #E; #E'; #w; #H; nelim H - [##1,2: #H1; ninversion H1 - [##1,8: #_; #K; (* non va ndestruct K; *) ncases (?:False); (* perche' due goal?*) /2/ - |##2,9: #X; #Y; #K; ncases (?:False); /2/ - |##3,10: #x; #y; #z; #w; #a; #b; #c; #d; #e; #K; ncases (?:False); /2/ - |##4,11: #x; #y; #z; #w; #a; #b; #K; ncases (?:False); /2/ - |##5,12: #x; #y; #z; #w; #a; #b; #K; ncases (?:False); /2/ - |##6,13: #x; #y; #K; ncases (?:False); /2/ - |##7,14: #x; #y; #z; #w; #a; #b; #c; #d; #K; ncases (?:False); /2/] -##| #H1; ninversion H1 - [ // - | #X; #Y; #K; ncases (?:False); /2/ - | #x; #y; #z; #w; #a; #b; #c; #d; #e; #K; ncases (?:False); /2/ - | #x; #y; #z; #w; #a; #b; #K; ncases (?:False); /2/ - | #x; #y; #z; #w; #a; #b; #K; ncases (?:False); /2/ - | #x; #y; #K; ncases (?:False); /2/ - | #x; #y; #z; #w; #a; #b; #c; #d; #K; ncases (?:False); /2/ ] -##| #H1; #H2; #H3; ninversion H3 - [ #_; #K; ncases (?:False); /2/ - | #X; #Y; #K; ncases (?:False); /2/ - | #x; #y; #z; #w; #a; #b; #c; #d; #e; #K; ncases (?:False); /2/ - | #x; #y; #z; #w; #a; #b; #K; ncases (?:False); /2/ - | #x; #y; #z; #w; #a; #b; #K; ncases (?:False); /2/ - | #x; #y; #K; ncases (?:False); /2/ - | #x; #y; #z; #w; #a; #b; #c; #d; #K; ncases (?:False); /2/ ] -##| #r1; #r2; #r1'; #r2'; #H1; #H2; #H3; #H4; #H5; #H6; \ No newline at end of file +notation "\fst term 90 x" non associative with precedence 90 for @{'fst $x}. \ No newline at end of file diff --git a/weblib/tutorial/re1.ma b/weblib/tutorial/re1.ma new file mode 100644 index 000000000..a32e29ba6 --- /dev/null +++ b/weblib/tutorial/re1.ma @@ -0,0 +1,755 @@ +(* + ||M|| This file is part of HELM, an Hypertextual, Electronic + ||A|| Library of Mathematics, developed at the Computer Science + ||T|| Department of the University of Bologna, Italy. + ||I|| + ||T|| + ||A|| This file is distributed under the terms of the + \ / GNU General Public License Version 2 + \ / + V_______________________________________________________________ *) + +include "arithmetics/nat.ma". +include "basics/list.ma". + +interpretation "iff" 'iff a b = (iff a b). + +record Alpha : Type[1] ≝ { carr :> Type[0]; + eqb: carr → carr → a href="cic:/matita/basics/bool/bool.ind(1,0,0)"bool/a; + eqb_true: ∀x,y. (eqb x y a title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/a a href="cic:/matita/basics/bool/bool.con(0,1,0)"true/a) a title="iff" href="cic:/fakeuri.def(1)"↔/a (x a title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/a y) +}. + +notation "a == b" non associative with precedence 45 for @{ 'eqb $a $b }. +interpretation "eqb" 'eqb a b = (eqb ? a b). + +definition word ≝ λS:a href="cic:/matita/tutorial/re/Alpha.ind(1,0,0)"Alpha/a.a href="cic:/matita/basics/list/list.ind(1,0,1)"list/a S. + +inductive re (S: a href="cic:/matita/tutorial/re/Alpha.ind(1,0,0)"Alpha/a) : Type[0] ≝ + z: re S + | e: re S + | s: S → re S + | c: re S → re S → re S + | o: re S → re S → re S + | k: re S → re S. + +notation < "a \sup ⋇" non associative with precedence 90 for @{ 'pk $a}. +notation > "a ^ *" non associative with precedence 90 for @{ 'pk $a}. +interpretation "star" 'pk a = (k ? a). +interpretation "or" 'plus a b = (o ? a b). + +notation "a · b" non associative with precedence 60 for @{ 'pc $a $b}. +interpretation "cat" 'pc a b = (c ? a b). + +(* to get rid of \middot +coercion c : ∀S:Alpha.∀p:re S. re S → re S ≝ c on _p : re ? to ∀_:?.?. *) + +notation < "a" non associative with precedence 90 for @{ 'ps $a}. +notation > "` term 90 a" non associative with precedence 90 for @{ 'ps $a}. +interpretation "atom" 'ps a = (s ? a). + +notation "ϵ" non associative with precedence 90 for @{ 'epsilon }. +interpretation "epsilon" 'epsilon = (e ?). + +notation "∅" non associative with precedence 90 for @{ 'empty }. +interpretation "empty" 'empty = (z ?). + +let rec flatten (S : a href="cic:/matita/tutorial/re/Alpha.ind(1,0,0)"Alpha/a) (l : a href="cic:/matita/basics/list/list.ind(1,0,1)"list/a (a href="cic:/matita/tutorial/re/word.def(3)"word/a S)) on l : a href="cic:/matita/tutorial/re/word.def(3)"word/a S ≝ +match l with [ nil ⇒ a title="nil" href="cic:/fakeuri.def(1)"[/a ] | cons w tl ⇒ w a title="append" href="cic:/fakeuri.def(1)"@/a flatten ? tl ]. + +let rec conjunct (S : a href="cic:/matita/tutorial/re/Alpha.ind(1,0,0)"Alpha/a) (l : a href="cic:/matita/basics/list/list.ind(1,0,1)"list/a (a href="cic:/matita/tutorial/re/word.def(3)"word/a S)) (r : a href="cic:/matita/tutorial/re/word.def(3)"word/a S → Prop) on l: Prop ≝ +match l with [ nil ⇒ a href="cic:/matita/basics/logic/True.ind(1,0,0)"True/a | cons w tl ⇒ r w a title="logical and" href="cic:/fakeuri.def(1)"∧/a conjunct ? tl r ]. + +definition empty_lang ≝ λS.λw:a href="cic:/matita/tutorial/re/word.def(3)"word/a S.a href="cic:/matita/basics/logic/False.ind(1,0,0)"False/a. +notation "{}" non associative with precedence 90 for @{'empty_lang}. +interpretation "empty lang" 'empty_lang = (empty_lang ?). + +definition sing_lang ≝ λS.λx,w:a href="cic:/matita/tutorial/re/word.def(3)"word/a S.xa title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/aw. +notation "{x}" non associative with precedence 90 for @{'sing_lang $x}. +interpretation "sing lang" 'sing_lang x = (sing_lang ? x). + +definition union : ∀S,l1,l2,w.Prop ≝ λS.λl1,l2.λw:a href="cic:/matita/tutorial/re/word.def(3)"word/a S.l1 w a title="logical or" href="cic:/fakeuri.def(1)"∨/a l2 w. +interpretation "union lang" 'union a b = (union ? a b). + +definition cat : ∀S,l1,l2,w.Prop ≝ + λS.λl1,l2.λw:a href="cic:/matita/tutorial/re/word.def(3)"word/a S.a title="exists" href="cic:/fakeuri.def(1)"∃/aw1,w2.w1 a title="append" href="cic:/fakeuri.def(1)"@/a w2 a title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/a w a title="logical and" href="cic:/fakeuri.def(1)"∧/a l1 w1 a title="logical and" href="cic:/fakeuri.def(1)"∧/a l2 w2. +interpretation "cat lang" 'pc a b = (cat ? a b). + +definition star ≝ λS.λl.λw:a href="cic:/matita/tutorial/re/word.def(3)"word/a S.a title="exists" href="cic:/fakeuri.def(1)"∃/alw.a href="cic:/matita/tutorial/re/flatten.fix(0,1,4)"flatten/a ? lw a title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/a w a title="logical and" href="cic:/fakeuri.def(1)"∧/a a href="cic:/matita/tutorial/re/conjunct.fix(0,1,4)"conjunct/a ? lw l. +interpretation "star lang" 'pk l = (star ? l). + +notation > "𝐋 term 70 E" non associative with precedence 75 for @{in_l ? $E}. + +let rec in_l (S : Alpha) (r : re S) on r : word S → Prop ≝ +match r with +[ z ⇒ {} +| e ⇒ { [ ] } +| s x ⇒ { [x] } +| c r1 r2 ⇒ 𝐋 r1 · 𝐋 r2 +| o r1 r2 ⇒ 𝐋 r1 ∪ 𝐋 r2 +| k r1 ⇒ (𝐋 r1) ^*]. + +notation "𝐋 term 70 E" non associative with precedence 75 for @{'in_l $E}. +interpretation "in_l" 'in_l E = (in_l ? E). +interpretation "in_l mem" 'mem w l = (in_l ? l w). + +notation "a || b" left associative with precedence 30 for @{'orb $a $b}. +interpretation "orb" 'orb a b = (orb a b). + +ndefinition if_then_else ≝ λT:Type[0].λe,t,f.match e return λ_.T with [ true ⇒ t | false ⇒ f]. +notation > "'if' term 19 e 'then' term 19 t 'else' term 19 f" non associative with precedence 19 for @{ 'if_then_else $e $t $f }. +notation < "'if' \nbsp term 19 e \nbsp 'then' \nbsp term 19 t \nbsp 'else' \nbsp term 90 f \nbsp" non associative with precedence 19 for @{ 'if_then_else $e $t $f }. +interpretation "if_then_else" 'if_then_else e t f = (if_then_else ? e t f). + +ninductive pitem (S: Alpha) : Type[0] ≝ + pz: pitem S + | pe: pitem S + | ps: S → pitem S + | pp: S → pitem S + | pc: pitem S → pitem S → pitem S + | po: pitem S → pitem S → pitem S + | pk: pitem S → pitem S. + +ndefinition pre ≝ λS.pitem S × bool. + +interpretation "pstar" 'pk a = (pk ? a). +interpretation "por" 'plus a b = (po ? a b). +interpretation "pcat" 'pc a b = (pc ? a b). +notation < ".a" non associative with precedence 90 for @{ 'pp $a}. +notation > "`. term 90 a" non associative with precedence 90 for @{ 'pp $a}. +interpretation "ppatom" 'pp a = (pp ? a). +(* to get rid of \middot *) +ncoercion pc : ∀S.∀p:pitem S. pitem S → pitem S ≝ pc on _p : pitem ? to ∀_:?.?. +interpretation "patom" 'ps a = (ps ? a). +interpretation "pepsilon" 'epsilon = (pe ?). +interpretation "pempty" 'empty = (pz ?). + +notation > "|term 19 e|" non associative with precedence 70 for @{forget ? $e}. +nlet rec forget (S: Alpha) (l : pitem S) on l: re S ≝ + match l with + [ pz ⇒ ∅ + | pe ⇒ ϵ + | ps x ⇒ `x + | pp x ⇒ `x + | pc E1 E2 ⇒ (|E1| · |E2|) + | po E1 E2 ⇒ (|E1| + |E2|) + | pk E ⇒ |E|^* ]. +notation < "|term 19 e|" non associative with precedence 70 for @{'forget $e}. +interpretation "forget" 'forget a = (forget ? a). + +notation "\fst term 90 x" non associative with precedence 90 for @{'fst $x}. +interpretation "fst" 'fst x = (fst ? ? x). +notation > "\snd term 90 x" non associative with precedence 90 for @{'snd $x}. +interpretation "snd" 'snd x = (snd ? ? x). + +notation > "𝐋\p\ term 70 E" non associative with precedence 75 for @{in_pl ? $E}. +nlet rec in_pl (S : Alpha) (r : pitem S) on r : word S → Prop ≝ +match r with +[ pz ⇒ {} +| pe ⇒ {} +| ps _ ⇒ {} +| pp x ⇒ { [x] } +| pc r1 r2 ⇒ 𝐋\p\ r1 · 𝐋 |r2| ∪ 𝐋\p\ r2 +| po r1 r2 ⇒ 𝐋\p\ r1 ∪ 𝐋\p\ r2 +| pk r1 ⇒ 𝐋\p\ r1 · 𝐋 (|r1|^* ) ]. +notation > "𝐋\p term 70 E" non associative with precedence 75 for @{'in_pl $E}. +notation "𝐋\sub(\p) term 70 E" non associative with precedence 75 for @{'in_pl $E}. +interpretation "in_pl" 'in_pl E = (in_pl ? E). +interpretation "in_pl mem" 'mem w l = (in_pl ? l w). + +ndefinition epsilon ≝ λS,b.if b then { ([ ] : word S) } else {}. + +interpretation "epsilon" 'epsilon = (epsilon ?). +notation < "ϵ b" non associative with precedence 90 for @{'app_epsilon $b}. +interpretation "epsilon lang" 'app_epsilon b = (epsilon ? b). + +ndefinition in_prl ≝ λS : Alpha.λp:pre S. 𝐋\p (\fst p) ∪ ϵ (\snd p). + +interpretation "in_prl mem" 'mem w l = (in_prl ? l w). +interpretation "in_prl" 'in_pl E = (in_prl ? E). + +nlemma append_eq_nil : ∀S.∀w1,w2:word S. w1 @ w2 = [ ] → w1 = [ ]. +#S w1; nelim w1; //. #x tl IH w2; nnormalize; #abs; ndestruct; nqed. + +(* lemma 12 *) +nlemma epsilon_in_true : ∀S.∀e:pre S. [ ] ∈ e ↔ \snd e = true. +#S r; ncases r; #e b; @; ##[##2: #H; nrewrite > H; @2; /2/; ##] ncases b;//; +nnormalize; *; ##[##2:*] nelim e; +##[ ##1,2: *; ##| #c; *; ##| #c; nnormalize; #; ndestruct; ##| ##7: #p H; +##| #r1 r2 H G; *; ##[##2: /3/ by or_intror] +##| #r1 r2 H1 H2; *; /3/ by or_intror, or_introl; ##] +*; #w1; *; #w2; *; *; #defw1; nrewrite > (append_eq_nil … w1 w2 …); /3/ by {};//; +nqed. + +nlemma not_epsilon_lp : ∀S:Alpha.∀e:pitem S. ¬ ((𝐋\p e) [ ]). +#S e; nelim e; nnormalize; /2/ by nmk; +##[ #; @; #; ndestruct; +##| #r1 r2 n1 n2; @; *; /2/; *; #w1; *; #w2; *; *; #H; + nrewrite > (append_eq_nil …H…); /2/; +##| #r1 r2 n1 n2; @; *; /2/; +##| #r n; @; *; #w1; *; #w2; *; *; #H; + nrewrite > (append_eq_nil …H…); /2/;##] +nqed. + +ndefinition lo ≝ λS:Alpha.λa,b:pre S.〈\fst a + \fst b,\snd a || \snd b〉. +notation "a ⊕ b" left associative with precedence 60 for @{'oplus $a $b}. +interpretation "oplus" 'oplus a b = (lo ? a b). + +ndefinition lc ≝ λS:Alpha.λbcast:∀S:Alpha.∀E:pitem S.pre S.λa,b:pre S. + match a with [ mk_pair e1 b1 ⇒ + match b1 with + [ false ⇒ 〈e1 · \fst b, \snd b〉 + | true ⇒ 〈e1 · \fst (bcast ? (\fst b)),\snd b || \snd (bcast ? (\fst b))〉]]. + +notation < "a ⊙ b" left associative with precedence 60 for @{'lc $op $a $b}. +interpretation "lc" 'lc op a b = (lc ? op a b). +notation > "a ⊙ b" left associative with precedence 60 for @{'lc eclose $a $b}. + +ndefinition lk ≝ λS:Alpha.λbcast:∀S:Alpha.∀E:pitem S.pre S.λa:pre S. + match a with [ mk_pair e1 b1 ⇒ + match b1 with + [ false ⇒ 〈e1^*, false〉 + | true ⇒ 〈(\fst (bcast ? e1))^*, true〉]]. + +notation < "a \sup ⊛" non associative with precedence 90 for @{'lk $op $a}. +interpretation "lk" 'lk op a = (lk ? op a). +notation > "a^⊛" non associative with precedence 90 for @{'lk eclose $a}. + +notation > "•" non associative with precedence 60 for @{eclose ?}. +nlet rec eclose (S: Alpha) (E: pitem S) on E : pre S ≝ + match E with + [ pz ⇒ 〈 ∅, false 〉 + | pe ⇒ 〈 ϵ, true 〉 + | ps x ⇒ 〈 `.x, false 〉 + | pp x ⇒ 〈 `.x, false 〉 + | po E1 E2 ⇒ •E1 ⊕ •E2 + | pc E1 E2 ⇒ •E1 ⊙ 〈 E2, false 〉 + | pk E ⇒ 〈(\fst (•E))^*,true〉]. +notation < "• x" non associative with precedence 60 for @{'eclose $x}. +interpretation "eclose" 'eclose x = (eclose ? x). +notation > "• x" non associative with precedence 60 for @{'eclose $x}. + +ndefinition reclose ≝ λS:Alpha.λp:pre S.let p' ≝ •\fst p in 〈\fst p',\snd p || \snd p'〉. +interpretation "reclose" 'eclose x = (reclose ? x). + +ndefinition eq_f1 ≝ λS.λa,b:word S → Prop.∀w.a w ↔ b w. +notation > "A =1 B" non associative with precedence 45 for @{'eq_f1 $A $B}. +notation "A =\sub 1 B" non associative with precedence 45 for @{'eq_f1 $A $B}. +interpretation "eq f1" 'eq_f1 a b = (eq_f1 ? a b). + +naxiom extP : ∀S.∀p,q:word S → Prop.(p =1 q) → p = q. + +nlemma epsilon_or : ∀S:Alpha.∀b1,b2. ϵ(b1 || b2) = ϵ b1 ∪ ϵ b2. ##[##2: napply S] +#S b1 b2; ncases b1; ncases b2; napply extP; #w; nnormalize; @; /2/; *; //; *; +nqed. + +nlemma cupA : ∀S.∀a,b,c:word S → Prop.a ∪ b ∪ c = a ∪ (b ∪ c). +#S a b c; napply extP; #w; nnormalize; @; *; /3/; *; /3/; nqed. + +nlemma cupC : ∀S. ∀a,b:word S → Prop.a ∪ b = b ∪ a. +#S a b; napply extP; #w; @; *; nnormalize; /2/; nqed. + +(* theorem 16: 2 *) +nlemma oplus_cup : ∀S:Alpha.∀e1,e2:pre S.𝐋\p (e1 ⊕ e2) = 𝐋\p e1 ∪ 𝐋\p e2. +#S r1; ncases r1; #e1 b1 r2; ncases r2; #e2 b2; +nwhd in ⊢ (??(??%)?); +nchange in ⊢(??%?) with (𝐋\p (e1 + e2) ∪ ϵ (b1 || b2)); +nchange in ⊢(??(??%?)?) with (𝐋\p (e1) ∪ 𝐋\p (e2)); +nrewrite > (epsilon_or S …); nrewrite > (cupA S (𝐋\p e1) …); +nrewrite > (cupC ? (ϵ b1) …); nrewrite < (cupA S (𝐋\p e2) …); +nrewrite > (cupC ? ? (ϵ b1) …); nrewrite < (cupA …); //; +nqed. + +nlemma odotEt : + ∀S.∀e1,e2:pitem S.∀b2. 〈e1,true〉 ⊙ 〈e2,b2〉 = 〈e1 · \fst (•e2),b2 || \snd (•e2)〉. +#S e1 e2 b2; nnormalize; ncases (•e2); //; nqed. + +nlemma LcatE : ∀S.∀e1,e2:pitem S.𝐋\p (e1 · e2) = 𝐋\p e1 · 𝐋 |e2| ∪ 𝐋\p e2. //; nqed. + +nlemma cup_dotD : ∀S.∀p,q,r:word S → Prop.(p ∪ q) · r = (p · r) ∪ (q · r). +#S p q r; napply extP; #w; nnormalize; @; +##[ *; #x; *; #y; *; *; #defw; *; /7/ by or_introl, or_intror, ex_intro, conj; +##| *; *; #x; *; #y; *; *; /7/ by or_introl, or_intror, ex_intro, conj; ##] +nqed. + +nlemma cup0 :∀S.∀p:word S → Prop.p ∪ {} = p. +#S p; napply extP; #w; nnormalize; @; /2/; *; //; *; nqed. + +nlemma erase_dot : ∀S.∀e1,e2:pitem S.𝐋 |e1 · e2| = 𝐋 |e1| · 𝐋 |e2|. +#S e1 e2; napply extP; nnormalize; #w; @; *; #w1; *; #w2; *; *; /7/ by ex_intro, conj; +nqed. + +nlemma erase_plus : ∀S.∀e1,e2:pitem S.𝐋 |e1 + e2| = 𝐋 |e1| ∪ 𝐋 |e2|. +#S e1 e2; napply extP; nnormalize; #w; @; *; /4/ by or_introl, or_intror; nqed. + +nlemma erase_star : ∀S.∀e1:pitem S.𝐋 |e1|^* = 𝐋 |e1^*|. //; nqed. + +ndefinition substract := λS.λp,q:word S → Prop.λw.p w ∧ ¬ q w. +interpretation "substract" 'minus a b = (substract ? a b). + +nlemma cup_sub: ∀S.∀a,b:word S → Prop. ¬ (a []) → a ∪ (b - {[]}) = (a ∪ b) - {[]}. +#S a b c; napply extP; #w; nnormalize; @; *; /4/; *; /4/; nqed. + +nlemma sub0 : ∀S.∀a:word S → Prop. a - {} = a. +#S a; napply extP; #w; nnormalize; @; /3/; *; //; nqed. + +nlemma subK : ∀S.∀a:word S → Prop. a - a = {}. +#S a; napply extP; #w; nnormalize; @; *; /2/; nqed. + +nlemma subW : ∀S.∀a,b:word S → Prop.∀w.(a - b) w → a w. +#S a b w; nnormalize; *; //; nqed. + +nlemma erase_bull : ∀S.∀a:pitem S. |\fst (•a)| = |a|. +#S a; nelim a; // by {}; +##[ #e1 e2 IH1 IH2; nchange in ⊢ (???%) with (|e1| · |e2|); + nrewrite < IH1; nrewrite < IH2; + nchange in ⊢ (??(??%)?) with (\fst (•e1 ⊙ 〈e2,false〉)); + ncases (•e1); #e3 b; ncases b; nnormalize; + ##[ ncases (•e2); //; ##| nrewrite > IH2; //] +##| #e1 e2 IH1 IH2; nchange in ⊢ (???%) with (|e1| + |e2|); + nrewrite < IH2; nrewrite < IH1; + nchange in ⊢ (??(??%)?) with (\fst (•e1 ⊕ •e2)); + ncases (•e1); ncases (•e2); //; +##| #e IH; nchange in ⊢ (???%) with (|e|^* ); nrewrite < IH; + nchange in ⊢ (??(??%)?) with (\fst (•e))^*; //; ##] +nqed. + +nlemma eta_lp : ∀S.∀p:pre S.𝐋\p p = 𝐋\p 〈\fst p, \snd p〉. +#S p; ncases p; //; nqed. + +nlemma epsilon_dot: ∀S.∀p:word S → Prop. {[]} · p = p. +#S e; napply extP; #w; nnormalize; @; ##[##2: #Hw; @[]; @w; /3/; ##] +*; #w1; *; #w2; *; *; #defw defw1 Hw2; nrewrite < defw; nrewrite < defw1; +napply Hw2; nqed. + +(* theorem 16: 1 → 3 *) +nlemma odot_dot_aux : ∀S.∀e1,e2: pre S. + 𝐋\p (•(\fst e2)) = 𝐋\p (\fst e2) ∪ 𝐋 |\fst e2| → + 𝐋\p (e1 ⊙ e2) = 𝐋\p e1 · 𝐋 |\fst e2| ∪ 𝐋\p e2. +#S e1 e2 th1; ncases e1; #e1' b1'; ncases b1'; +##[ nwhd in ⊢ (??(??%)?); nletin e2' ≝ (\fst e2); nletin b2' ≝ (\snd e2); + nletin e2'' ≝ (\fst (•(\fst e2))); nletin b2'' ≝ (\snd (•(\fst e2))); + nchange in ⊢ (??%?) with (?∪?); + nchange in ⊢ (??(??%?)?) with (?∪?); + nchange in match (𝐋\p 〈?,?〉) with (?∪?); + nrewrite > (epsilon_or …); nrewrite > (cupC ? (ϵ ?)…); + nrewrite > (cupA …);nrewrite < (cupA ?? (ϵ?)…); + nrewrite > (?: 𝐋\p e2'' ∪ ϵ b2'' = 𝐋\p e2' ∪ 𝐋 |e2'|); ##[##2: + nchange with (𝐋\p 〈e2'',b2''〉 = 𝐋\p e2' ∪ 𝐋 |e2'|); + ngeneralize in match th1; + nrewrite > (eta_lp…); #th1; nrewrite > th1; //;##] + nrewrite > (eta_lp ? e2); + nchange in match (𝐋\p 〈\fst e2,?〉) with (𝐋\p e2'∪ ϵ b2'); + nrewrite > (cup_dotD …); nrewrite > (epsilon_dot…); + nrewrite > (cupC ? (𝐋\p e2')…); nrewrite > (cupA…);nrewrite > (cupA…); + nrewrite < (erase_bull S e2') in ⊢ (???(??%?)); //; +##| ncases e2; #e2' b2'; nchange in match (〈e1',false〉⊙?) with 〈?,?〉; + nchange in match (𝐋\p ?) with (?∪?); + nchange in match (𝐋\p (e1'·?)) with (?∪?); + nchange in match (𝐋\p 〈e1',?〉) with (?∪?); + nrewrite > (cup0…); + nrewrite > (cupA…); //;##] +nqed. + +nlemma sub_dot_star : + ∀S.∀X:word S → Prop.∀b. (X - ϵ b) · X^* ∪ {[]} = X^*. +#S X b; napply extP; #w; @; +##[ *; ##[##2: nnormalize; #defw; nrewrite < defw; @[]; @; //] + *; #w1; *; #w2; *; *; #defw sube; *; #lw; *; #flx cj; + @ (w1 :: lw); nrewrite < defw; nrewrite < flx; @; //; + @; //; napply (subW … sube); +##| *; #wl; *; #defw Pwl; nrewrite < defw; nelim wl in Pwl; ##[ #_; @2; //] + #w' wl' IH; *; #Pw' IHp; nlapply (IH IHp); *; + ##[ *; #w1; *; #w2; *; *; #defwl' H1 H2; + @; ncases b in H1; #H1; + ##[##2: nrewrite > (sub0…); @w'; @(w1@w2); + nrewrite > (associative_append ? w' w1 w2); + nrewrite > defwl'; @; ##[@;//] @(wl'); @; //; + ##| ncases w' in Pw'; + ##[ #ne; @w1; @w2; nrewrite > defwl'; @; //; @; //; + ##| #x xs Px; @(x::xs); @(w1@w2); + nrewrite > (defwl'); @; ##[@; //; @; //; @; nnormalize; #; ndestruct] + @wl'; @; //; ##] ##] + ##| #wlnil; nchange in match (flatten ? (w'::wl')) with (w' @ flatten ? wl'); + nrewrite < (wlnil); nrewrite > (append_nil…); ncases b; + ##[ ncases w' in Pw'; /2/; #x xs Pxs; @; @(x::xs); @([]); + nrewrite > (append_nil…); @; ##[ @; //;@; //; nnormalize; @; #; ndestruct] + @[]; @; //; + ##| @; @w'; @[]; nrewrite > (append_nil…); @; ##[##2: @[]; @; //] + @; //; @; //; @; *;##]##]##] +nqed. + +(* theorem 16: 1 *) +alias symbol "pc" (instance 13) = "cat lang". +alias symbol "in_pl" (instance 23) = "in_pl". +alias symbol "in_pl" (instance 5) = "in_pl". +alias symbol "eclose" (instance 21) = "eclose". +ntheorem bull_cup : ∀S:Alpha. ∀e:pitem S. 𝐋\p (•e) = 𝐋\p e ∪ 𝐋 |e|. +#S e; nelim e; //; + ##[ #a; napply extP; #w; nnormalize; @; *; /3/ by or_introl, or_intror; + ##| #a; napply extP; #w; nnormalize; @; *; /3/ by or_introl; *; + ##| #e1 e2 IH1 IH2; + nchange in ⊢ (??(??(%))?) with (•e1 ⊙ 〈e2,false〉); + nrewrite > (odot_dot_aux S (•e1) 〈e2,false〉 IH2); + nrewrite > (IH1 …); nrewrite > (cup_dotD …); + nrewrite > (cupA …); nrewrite > (cupC ?? (𝐋\p ?) …); + nchange in match (𝐋\p 〈?,?〉) with (𝐋\p e2 ∪ {}); nrewrite > (cup0 …); + nrewrite < (erase_dot …); nrewrite < (cupA …); //; + ##| #e1 e2 IH1 IH2; + nchange in match (•(?+?)) with (•e1 ⊕ •e2); nrewrite > (oplus_cup …); + nrewrite > (IH1 …); nrewrite > (IH2 …); nrewrite > (cupA …); + nrewrite > (cupC ? (𝐋\p e2)…);nrewrite < (cupA ??? (𝐋\p e2)…); + nrewrite > (cupC ?? (𝐋\p e2)…); nrewrite < (cupA …); + nrewrite < (erase_plus …); //. + ##| #e; nletin e' ≝ (\fst (•e)); nletin b' ≝ (\snd (•e)); #IH; + nchange in match (𝐋\p ?) with (𝐋\p 〈e'^*,true〉); + nchange in match (𝐋\p ?) with (𝐋\p (e'^* ) ∪ {[ ]}); + nchange in ⊢ (??(??%?)?) with (𝐋\p e' · 𝐋 |e'|^* ); + nrewrite > (erase_bull…e); + nrewrite > (erase_star …); + nrewrite > (?: 𝐋\p e' = 𝐋\p e ∪ (𝐋 |e| - ϵ b')); ##[##2: + nchange in IH : (??%?) with (𝐋\p e' ∪ ϵ b'); ncases b' in IH; + ##[ #IH; nrewrite > (cup_sub…); //; nrewrite < IH; + nrewrite < (cup_sub…); //; nrewrite > (subK…); nrewrite > (cup0…);//; + ##| nrewrite > (sub0 …); #IH; nrewrite < IH; nrewrite > (cup0 …);//; ##]##] + nrewrite > (cup_dotD…); nrewrite > (cupA…); + nrewrite > (?: ((?·?)∪{[]} = 𝐋 |e^*|)); //; + nchange in match (𝐋 |e^*|) with ((𝐋 |e|)^* ); napply sub_dot_star;##] + nqed. + +(* theorem 16: 3 *) +nlemma odot_dot: + ∀S.∀e1,e2: pre S. 𝐋\p (e1 ⊙ e2) = 𝐋\p e1 · 𝐋 |\fst e2| ∪ 𝐋\p e2. +#S e1 e2; napply odot_dot_aux; napply (bull_cup S (\fst e2)); nqed. + +nlemma dot_star_epsilon : ∀S.∀e:re S.𝐋 e · 𝐋 e^* ∪ {[]} = 𝐋 e^*. +#S e; napply extP; #w; nnormalize; @; +##[ *; ##[##2: #H; nrewrite < H; @[]; /3/] *; #w1; *; #w2; + *; *; #defw Hw1; *; #wl; *; #defw2 Hwl; @(w1 :: wl); + nrewrite < defw; nrewrite < defw2; @; //; @;//; +##| *; #wl; *; #defw Hwl; ncases wl in defw Hwl; ##[#defw; #; @2; nrewrite < defw; //] + #x xs defw; *; #Hx Hxs; @; @x; @(flatten ? xs); nrewrite < defw; + @; /2/; @xs; /2/;##] + nqed. + +nlemma nil_star : ∀S.∀e:re S. [ ] ∈ e^*. +#S e; @[]; /2/; nqed. + +nlemma cupID : ∀S.∀l:word S → Prop.l ∪ l = l. +#S l; napply extP; #w; @; ##[*]//; #; @; //; nqed. + +nlemma cup_star_nil : ∀S.∀l:word S → Prop. l^* ∪ {[]} = l^*. +#S a; napply extP; #w; @; ##[*; //; #H; nrewrite < H; @[]; @; //] #;@; //;nqed. + +nlemma rcanc_sing : ∀S.∀A,C:word S → Prop.∀b:word S . + ¬ (A b) → A ∪ { (b) } = C → A = C - { (b) }. +#S A C b nbA defC; nrewrite < defC; napply extP; #w; @; +##[ #Aw; /3/| *; *; //; #H nH; ncases nH; #abs; nlapply (abs H); *] +nqed. + +(* theorem 16: 4 *) +nlemma star_dot: ∀S.∀e:pre S. 𝐋\p (e^⊛) = 𝐋\p e · (𝐋 |\fst e|)^*. +#S p; ncases p; #e b; ncases b; +##[ nchange in match (〈e,true〉^⊛) with 〈?,?〉; + nletin e' ≝ (\fst (•e)); nletin b' ≝ (\snd (•e)); + nchange in ⊢ (??%?) with (?∪?); + nchange in ⊢ (??(??%?)?) with (𝐋\p e' · 𝐋 |e'|^* ); + nrewrite > (?: 𝐋\p e' = 𝐋\p e ∪ (𝐋 |e| - ϵ b' )); ##[##2: + nlapply (bull_cup ? e); #bc; + nchange in match (𝐋\p (•e)) in bc with (?∪?); + nchange in match b' in bc with b'; + ncases b' in bc; ##[##2: nrewrite > (cup0…); nrewrite > (sub0…); //] + nrewrite > (cup_sub…); ##[napply rcanc_sing] //;##] + nrewrite > (cup_dotD…); nrewrite > (cupA…);nrewrite > (erase_bull…); + nrewrite > (sub_dot_star…); + nchange in match (𝐋\p 〈?,?〉) with (?∪?); + nrewrite > (cup_dotD…); nrewrite > (epsilon_dot…); //; +##| nwhd in match (〈e,false〉^⊛); nchange in match (𝐋\p 〈?,?〉) with (?∪?); + nrewrite > (cup0…); + nchange in ⊢ (??%?) with (𝐋\p e · 𝐋 |e|^* ); + nrewrite < (cup0 ? (𝐋\p e)); //;##] +nqed. + +nlet rec pre_of_re (S : Alpha) (e : re S) on e : pitem S ≝ + match e with + [ z ⇒ pz ? + | e ⇒ pe ? + | s x ⇒ ps ? x + | c e1 e2 ⇒ pc ? (pre_of_re ? e1) (pre_of_re ? e2) + | o e1 e2 ⇒ po ? (pre_of_re ? e1) (pre_of_re ? e2) + | k e1 ⇒ pk ? (pre_of_re ? e1)]. + +nlemma notFalse : ¬False. @; //; nqed. + +nlemma dot0 : ∀S.∀A:word S → Prop. {} · A = {}. +#S A; nnormalize; napply extP; #w; @; ##[##2: *] +*; #w1; *; #w2; *; *; //; nqed. + +nlemma Lp_pre_of_re : ∀S.∀e:re S. 𝐋\p (pre_of_re ? e) = {}. +#S e; nelim e; ##[##1,2,3: //] +##[ #e1 e2 H1 H2; nchange in match (𝐋\p (pre_of_re S (e1 e2))) with (?∪?); + nrewrite > H1; nrewrite > H2; nrewrite > (dot0…); nrewrite > (cupID…);// +##| #e1 e2 H1 H2; nchange in match (𝐋\p (pre_of_re S (e1+e2))) with (?∪?); + nrewrite > H1; nrewrite > H2; nrewrite > (cupID…); // +##| #e1 H1; nchange in match (𝐋\p (pre_of_re S (e1^* ))) with (𝐋\p (pre_of_re ??) · ?); + nrewrite > H1; napply dot0; ##] +nqed. + +nlemma erase_pre_of_reK : ∀S.∀e. 𝐋 |pre_of_re S e| = 𝐋 e. +#S A; nelim A; //; +##[ #e1 e2 H1 H2; nchange in match (𝐋 (e1 · e2)) with (𝐋 e1·?); + nrewrite < H1; nrewrite < H2; // +##| #e1 e2 H1 H2; nchange in match (𝐋 (e1 + e2)) with (𝐋 e1 ∪ ?); + nrewrite < H1; nrewrite < H2; // +##| #e1 H1; nchange in match (𝐋 (e1^* )) with ((𝐋 e1)^* ); + nrewrite < H1; //] +nqed. + +(* corollary 17 *) +nlemma L_Lp_bull : ∀S.∀e:re S.𝐋 e = 𝐋\p (•pre_of_re ? e). +#S e; nrewrite > (bull_cup…); nrewrite > (Lp_pre_of_re…); +nrewrite > (cupC…); nrewrite > (cup0…); nrewrite > (erase_pre_of_reK…); //; +nqed. + +nlemma Pext : ∀S.∀f,g:word S → Prop. f = g → ∀w.f w → g w. +#S f g H; nrewrite > H; //; nqed. + +(* corollary 18 *) +ntheorem bull_true_epsilon : ∀S.∀e:pitem S. \snd (•e) = true ↔ [ ] ∈ |e|. +#S e; @; +##[ #defsnde; nlapply (bull_cup ? e); nchange in match (𝐋\p (•e)) with (?∪?); + nrewrite > defsnde; #H; + nlapply (Pext ??? H [ ] ?); ##[ @2; //] *; //; + +STOP + +notation > "\move term 90 x term 90 E" +non associative with precedence 60 for @{move ? $x $E}. +nlet rec move (S: Alpha) (x:S) (E: pitem S) on E : pre S ≝ + match E with + [ pz ⇒ 〈 ∅, false 〉 + | pe ⇒ 〈 ϵ, false 〉 + | ps y ⇒ 〈 `y, false 〉 + | pp y ⇒ 〈 `y, x == y 〉 + | po e1 e2 ⇒ \move x e1 ⊕ \move x e2 + | pc e1 e2 ⇒ \move x e1 ⊙ \move x e2 + | pk e ⇒ (\move x e)^⊛ ]. +notation < "\move\shy x\shy E" non associative with precedence 60 for @{'move $x $E}. +notation > "\move term 90 x term 90 E" non associative with precedence 60 for @{'move $x $E}. +interpretation "move" 'move x E = (move ? x E). + +ndefinition rmove ≝ λS:Alpha.λx:S.λe:pre S. \move x (\fst e). +interpretation "rmove" 'move x E = (rmove ? x E). + +nlemma XXz : ∀S:Alpha.∀w:word S. w ∈ ∅ → False. +#S w abs; ninversion abs; #; ndestruct; +nqed. + + +nlemma XXe : ∀S:Alpha.∀w:word S. w .∈ ϵ → False. +#S w abs; ninversion abs; #; ndestruct; +nqed. + +nlemma XXze : ∀S:Alpha.∀w:word S. w .∈ (∅ · ϵ) → False. +#S w abs; ninversion abs; #; ndestruct; /2/ by XXz,XXe; +nqed. + + +naxiom in_move_cat: + ∀S.∀w:word S.∀x.∀E1,E2:pitem S. w .∈ \move x (E1 · E2) → + (∃w1.∃w2. w = w1@w2 ∧ w1 .∈ \move x E1 ∧ w2 ∈ .|E2|) ∨ w .∈ \move x E2. +#S w x e1 e2 H; nchange in H with (w .∈ \move x e1 ⊙ \move x e2); +ncases e1 in H; ncases e2; +##[##1: *; ##[*; nnormalize; #; ndestruct] + #H; ninversion H; ##[##1,4,5,6: nnormalize; #; ndestruct] + nnormalize; #; ndestruct; ncases (?:False); /2/ by XXz,XXze; +##|##2: *; ##[*; nnormalize; #; ndestruct] + #H; ninversion H; ##[##1,4,5,6: nnormalize; #; ndestruct] + nnormalize; #; ndestruct; ncases (?:False); /2/ by XXz,XXze; +##| #r; *; ##[ *; nnormalize; #; ndestruct] + #H; ninversion H; ##[##1,4,5,6: nnormalize; #; ndestruct] + ##[##2: nnormalize; #; ndestruct; @2; @2; //.##] + nnormalize; #; ndestruct; ncases (?:False); /2/ by XXz; +##| #y; *; ##[ *; nnormalize; #defw defx; ndestruct; @2; @1; /2/ by conj;##] + #H; ninversion H; nnormalize; #; ndestruct; + ##[ncases (?:False); /2/ by XXz] /3/ by or_intror; +##| #r1 r2; *; ##[ *; #defw] + ... +nqed. + +ntheorem move_ok: + ∀S:Alpha.∀E:pre S.∀a,w.w .∈ \move a E ↔ (a :: w) .∈ E. +#S E; ncases E; #r b; nelim r; +##[##1,2: #a w; @; + ##[##1,3: nnormalize; *; ##[##1,3: *; #; ndestruct; ##| #abs; ncases (XXz … abs); ##] + #H; ninversion H; #; ndestruct; + ##|##*:nnormalize; *; ##[##1,3: *; #; ndestruct; ##| #H1; ncases (XXz … H1); ##] + #H; ninversion H; #; ndestruct;##] +##|#a c w; @; nnormalize; ##[*; ##[*; #; ndestruct; ##] #abs; ninversion abs; #; ndestruct;##] + *; ##[##2: #abs; ninversion abs; #; ndestruct; ##] *; #; ndestruct; +##|#a c w; @; nnormalize; + ##[ *; ##[ *; #defw; nrewrite > defw; #ca; @2; nrewrite > (eqb_t … ca); @; ##] + #H; ninversion H; #; ndestruct; + ##| *; ##[ *; #; ndestruct; ##] #H; ninversion H; ##[##2,3,4,5,6: #; ndestruct] + #d defw defa; ndestruct; @1; @; //; nrewrite > (eqb_true S d d); //. ##] +##|#r1 r2 H1 H2 a w; @; + ##[ #H; ncases (in_move_cat … H); + ##[ *; #w1; *; #w2; *; *; #defw w1m w2m; + ncases (H1 a w1); #H1w1; #_; nlapply (H1w1 w1m); #good; + nrewrite > defw; @2; @2 (a::w1); //; ncases good; ##[ *; #; ndestruct] //. + ##| + ... +##| +##| +##] +nqed. + + +notation > "x ↦* E" non associative with precedence 60 for @{move_star ? $x $E}. +nlet rec move_star (S : decidable) w E on w : bool × (pre S) ≝ + match w with + [ nil ⇒ E + | cons x w' ⇒ w' ↦* (x ↦ \snd E)]. + +ndefinition in_moves ≝ λS:decidable.λw.λE:bool × (pre S). \fst(w ↦* E). + +ncoinductive equiv (S:decidable) : bool × (pre S) → bool × (pre S) → Prop ≝ + mk_equiv: + ∀E1,E2: bool × (pre S). + \fst E1 = \fst E2 → + (∀x. equiv S (x ↦ \snd E1) (x ↦ \snd E2)) → + equiv S E1 E2. + +ndefinition NAT: decidable. + @ nat eqb; /2/. +nqed. + +include "hints_declaration.ma". + +alias symbol "hint_decl" (instance 1) = "hint_decl_Type1". +unification hint 0 ≔ ; X ≟ NAT ⊢ carr X ≡ nat. + +ninductive unit: Type[0] ≝ I: unit. + +nlet corec foo_nop (b: bool): + equiv ? + 〈 b, pc ? (ps ? 0) (pk ? (pc ? (ps ? 1) (ps ? 0))) 〉 + 〈 b, pc ? (pk ? (pc ? (ps ? 0) (ps ? 1))) (ps ? 0) 〉 ≝ ?. + @; //; #x; ncases x + [ nnormalize in ⊢ (??%%); napply (foo_nop false) + | #y; ncases y + [ nnormalize in ⊢ (??%%); napply (foo_nop false) + | #w; nnormalize in ⊢ (??%%); napply (foo_nop false) ]##] +nqed. + +(* +nlet corec foo (a: unit): + equiv NAT + (eclose NAT (pc ? (ps ? 0) (pk ? (pc ? (ps ? 1) (ps ? 0))))) + (eclose NAT (pc ? (pk ? (pc ? (ps ? 0) (ps ? 1))) (ps ? 0))) +≝ ?. + @; + ##[ nnormalize; // + ##| #x; ncases x + [ nnormalize in ⊢ (??%%); + nnormalize in foo: (? → ??%%); + @; //; #y; ncases y + [ nnormalize in ⊢ (??%%); napply foo_nop + | #y; ncases y + [ nnormalize in ⊢ (??%%); + + ##| #z; nnormalize in ⊢ (??%%); napply foo_nop ]##] + ##| #y; nnormalize in ⊢ (??%%); napply foo_nop + ##] +nqed. +*) + +ndefinition test1 : pre ? ≝ ❨ `0 | `1 ❩^* `0. +ndefinition test2 : pre ? ≝ ❨ (`0`1)^* `0 | (`0`1)^* `1 ❩. +ndefinition test3 : pre ? ≝ (`0 (`0`1)^* `1)^*. + + +nlemma foo: in_moves ? [0;0;1;0;1;1] (ɛ test3) = true. + nnormalize in match test3; + nnormalize; +//; +nqed. + +(**********************************************************) + +ninductive der (S: Type[0]) (a: S) : re S → re S → CProp[0] ≝ + der_z: der S a (z S) (z S) + | der_e: der S a (e S) (z S) + | der_s1: der S a (s S a) (e ?) + | der_s2: ∀b. a ≠ b → der S a (s S b) (z S) + | der_c1: ∀e1,e2,e1',e2'. in_l S [] e1 → der S a e1 e1' → der S a e2 e2' → + der S a (c ? e1 e2) (o ? (c ? e1' e2) e2') + | der_c2: ∀e1,e2,e1'. Not (in_l S [] e1) → der S a e1 e1' → + der S a (c ? e1 e2) (c ? e1' e2) + | der_o: ∀e1,e2,e1',e2'. der S a e1 e1' → der S a e2 e2' → + der S a (o ? e1 e2) (o ? e1' e2'). + +nlemma eq_rect_CProp0_r: + ∀A.∀a,x.∀p:eq ? x a.∀P: ∀x:A. eq ? x a → CProp[0]. P a (refl A a) → P x p. + #A; #a; #x; #p; ncases p; #P; #H; nassumption. +nqed. + +nlemma append1: ∀A.∀a:A.∀l. [a] @ l = a::l. //. nqed. + +naxiom in_l1: ∀S,r1,r2,w. in_l S [ ] r1 → in_l S w r2 → in_l S w (c S r1 r2). +(* #S; #r1; #r2; #w; nelim r1 + [ #K; ninversion K + | #H1; #H2; napply (in_c ? []); // + | (* tutti casi assurdi *) *) + +ninductive in_l' (S: Type[0]) : word S → re S → CProp[0] ≝ + in_l_empty1: ∀E.in_l S [] E → in_l' S [] E + | in_l_cons: ∀a,w,e,e'. in_l' S w e' → der S a e e' → in_l' S (a::w) e. + +ncoinductive eq_re (S: Type[0]) : re S → re S → CProp[0] ≝ + mk_eq_re: ∀E1,E2. + (in_l S [] E1 → in_l S [] E2) → + (in_l S [] E2 → in_l S [] E1) → + (∀a,E1',E2'. der S a E1 E1' → der S a E2 E2' → eq_re S E1' E2') → + eq_re S E1 E2. + +(* serve il lemma dopo? *) +ntheorem eq_re_is_eq: ∀S.∀E1,E2. eq_re S E1 E2 → ∀w. in_l ? w E1 → in_l ? w E2. + #S; #E1; #E2; #H1; #w; #H2; nelim H2 in E2 H1 ⊢ % + [ #r; #K (* ok *) + | #a; #w; #R1; #R2; #K1; #K2; #K3; #R3; #K4; @2 R2; //; ncases K4; + +(* IL VICEVERSA NON VALE *) +naxiom in_l_to_in_l: ∀S,w,E. in_l' S w E → in_l S w E. +(* #S; #w; #E; #H; nelim H + [ // + | #a; #w'; #r; #r'; #H1; (* e si cade qua sotto! *) + ] +nqed. *) + +ntheorem der1: ∀S,a,e,e',w. der S a e e' → in_l S w e' → in_l S (a::w) e. + #S; #a; #E; #E'; #w; #H; nelim H + [##1,2: #H1; ninversion H1 + [##1,8: #_; #K; (* non va ndestruct K; *) ncases (?:False); (* perche' due goal?*) /2/ + |##2,9: #X; #Y; #K; ncases (?:False); /2/ + |##3,10: #x; #y; #z; #w; #a; #b; #c; #d; #e; #K; ncases (?:False); /2/ + |##4,11: #x; #y; #z; #w; #a; #b; #K; ncases (?:False); /2/ + |##5,12: #x; #y; #z; #w; #a; #b; #K; ncases (?:False); /2/ + |##6,13: #x; #y; #K; ncases (?:False); /2/ + |##7,14: #x; #y; #z; #w; #a; #b; #c; #d; #K; ncases (?:False); /2/] +##| #H1; ninversion H1 + [ // + | #X; #Y; #K; ncases (?:False); /2/ + | #x; #y; #z; #w; #a; #b; #c; #d; #e; #K; ncases (?:False); /2/ + | #x; #y; #z; #w; #a; #b; #K; ncases (?:False); /2/ + | #x; #y; #z; #w; #a; #b; #K; ncases (?:False); /2/ + | #x; #y; #K; ncases (?:False); /2/ + | #x; #y; #z; #w; #a; #b; #c; #d; #K; ncases (?:False); /2/ ] +##| #H1; #H2; #H3; ninversion H3 + [ #_; #K; ncases (?:False); /2/ + | #X; #Y; #K; ncases (?:False); /2/ + | #x; #y; #z; #w; #a; #b; #c; #d; #e; #K; ncases (?:False); /2/ + | #x; #y; #z; #w; #a; #b; #K; ncases (?:False); /2/ + | #x; #y; #z; #w; #a; #b; #K; ncases (?:False); /2/ + | #x; #y; #K; ncases (?:False); /2/ + | #x; #y; #z; #w; #a; #b; #c; #d; #K; ncases (?:False); /2/ ] +##| #r1; #r2; #r1'; #r2'; #H1; #H2; #H3; #H4; #H5; #H6; \ No newline at end of file diff --git a/weblib/tutorial/sets.ma b/weblib/tutorial/sets.ma new file mode 100644 index 000000000..58e349509 --- /dev/null +++ b/weblib/tutorial/sets.ma @@ -0,0 +1,97 @@ +include "basics/logic.ma". + +(* Given a universe A, we can consider sets of elements of type A by means of their +characteristic predicates A → Prop. *) + +definition set ≝ λA:Type[0].A → Prop. + +(* For instance, the empty set is the set defined by an always False predicate *) + +definition empty : ∀A.a href="cic:/matita/tutorial/chapter4/set.def(1)"set/a A ≝ λA.λa:A.a href="cic:/matita/basics/logic/False.ind(1,0,0)"False/a. + +(* the singleton set {a} can be defined by the characteristic predicate stating +equality with a *) + +definition singleton: ∀A.A → a href="cic:/matita/tutorial/chapter4/set.def(1)"set/a A ≝ λA.λa,x.aa title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/ax. + +(* Complement, union and intersection are easily defined, by means of logical +connectives *) + +definition complement: ∀A. a href="cic:/matita/tutorial/chapter4/set.def(1)"set/a A → a href="cic:/matita/tutorial/chapter4/set.def(1)"set/a A ≝ λA,P,x.a title="logical not" href="cic:/fakeuri.def(1)"¬/a(P x). + +definition intersection: ∀A. a href="cic:/matita/tutorial/chapter4/set.def(1)"set/a A → a href="cic:/matita/tutorial/chapter4/set.def(1)"set/a A → a href="cic:/matita/tutorial/chapter4/set.def(1)"set/a A ≝ λA,P,Q,x.(P x) a title="logical and" href="cic:/fakeuri.def(1)"∧/a (Q x). + +definition union: ∀A. a href="cic:/matita/tutorial/chapter4/set.def(1)"set/a A → a href="cic:/matita/tutorial/chapter4/set.def(1)"set/a A → a href="cic:/matita/tutorial/chapter4/set.def(1)"set/a A ≝ λA,P,Q,x.(P x) a title="logical or" href="cic:/fakeuri.def(1)"∨/a (Q x). + + + + + + + + (* The reader could probably wonder what is the difference between Prop and bool. +In fact, they are quite distinct entities. In type theory, all objects are structured +in a three levels hierarchy + t : A : s +where, t is a term, A is a type, and s is called a sort. Sorts are special, primitive +constants used to give a type to types. Now, Prop is a primitive sort, while bool is +just a user defined data type (whose sort his Type[0]). In particular, Prop is the +sort of Propositions: its elements are logical statements in the usual sense. The important +point is that statements are inhabited by their proofs: a triple of the kind + p : Q : Prop +should be read as p is a proof of the proposition Q.*) + + + +include "arithmetics/nat.ma". +include "basics/list.ma". + +interpretation "iff" 'iff a b = (iff a b). + +record Alpha : Type[1] ≝ { carr :> Type[0]; + eqb: carr → carr → a href="cic:/matita/basics/bool/bool.ind(1,0,0)"bool/a; + eqb_true: ∀x,y. (eqb x y a title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/a a href="cic:/matita/basics/bool/bool.con(0,1,0)"true/a) a title="iff" href="cic:/fakeuri.def(1)"↔/a (x a title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/a y) +}. + +notation "a == b" non associative with precedence 45 for @{ 'eqb $a $b }. +interpretation "eqb" 'eqb a b = (eqb ? a b). + +definition word ≝ λS:a href="cic:/matita/tutorial/re/Alpha.ind(1,0,0)"Alpha/a.a href="cic:/matita/basics/list/list.ind(1,0,1)"list/a S. + +inductive re (S: a href="cic:/matita/tutorial/re/Alpha.ind(1,0,0)"Alpha/a) : Type[0] ≝ + z: re S + | e: re S + | s: S → re S + | c: re S → re S → re S + | o: re S → re S → re S + | k: re S → re S. + +notation < "a \sup ⋇" non associative with precedence 90 for @{ 'pk $a}. +notation > "a ^ *" non associative with precedence 90 for @{ 'pk $a}. +interpretation "star" 'pk a = (k ? a). +interpretation "or" 'plus a b = (o ? a b). + +notation "a · b" non associative with precedence 60 for @{ 'pc $a $b}. +interpretation "cat" 'pc a b = (c ? a b). + +(* to get rid of \middot +coercion c : ∀S:Alpha.∀p:re S. re S → re S ≝ c on _p : re ? to ∀_:?.?. *) + +notation < "a" non associative with precedence 90 for @{ 'ps $a}. +notation > "` term 90 a" non associative with precedence 90 for @{ 'ps $a}. +interpretation "atom" 'ps a = (s ? a). + +notation "ϵ" non associative with precedence 90 for @{ 'epsilon }. +interpretation "epsilon" 'epsilon = (e ?). + +notation "∅" non associative with precedence 90 for @{ 'empty }. +interpretation "empty" 'empty = (z ?). + +let rec flatten (S : a href="cic:/matita/tutorial/re/Alpha.ind(1,0,0)"Alpha/a) (l : a href="cic:/matita/basics/list/list.ind(1,0,1)"list/a (a href="cic:/matita/tutorial/re/word.def(3)"word/a S)) on l : a href="cic:/matita/tutorial/re/word.def(3)"word/a S ≝ +match l with [ nil ⇒ a title="nil" href="cic:/fakeuri.def(1)"[/a ] | cons w tl ⇒ w a title="append" href="cic:/fakeuri.def(1)"@/a flatten ? tl ]. + +let rec conjunct (S : a href="cic:/matita/tutorial/re/Alpha.ind(1,0,0)"Alpha/a) (l : a href="cic:/matita/basics/list/list.ind(1,0,1)"list/a (a href="cic:/matita/tutorial/re/word.def(3)"word/a S)) (r : a href="cic:/matita/tutorial/re/word.def(3)"word/a S → Prop) on l: Prop ≝ +match l with [ nil ⇒ a href="cic:/matita/basics/logic/True.ind(1,0,0)"True/a | cons w tl ⇒ r w a title="logical and" href="cic:/fakeuri.def(1)"∧/a conjunct ? tl r ]. + +definition empty_lang ≝ λS.λw:a href="cic:/matita/tutorial/re/word.def(3)"word/a S.a href="cic:/matita/basics/logic/False.ind(1,0,0)"False/a. +notation "{}" non associative with precedence 90 f \ No newline at end of file