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(* -*- mode: coq; coq-prog-args: ("-emacs" "-R" "." "Fiat" "-top" "BooleanRecognizerMin" "-R" "." "Top") -*- *)
(* File reduced by coq-bug-finder from original input, then from 2475 lines to 729 lines, then from 746 lines to 658 lines, then from 675 lines to 658 lines *)
(* coqc version 8.5beta3 (November 2015) compiled on Nov 11 2015 18:23:0 with OCaml 4.01.0
coqtop version 8.5beta3 (November 2015) *)
(* Variable P : forall n m : nat, n = m -> Prop. *)
(* Axiom Prefl : forall n : nat, P n n eq_refl. *)
Axiom proof_admitted : False.
Tactic Notation "admit" := case proof_admitted.
Require Coq.Program.Program.
Require Coq.Strings.String.
Require Coq.omega.Omega.
Module Export Fiat_DOT_Common.
Module Export Fiat.
Module Common.
Import Coq.Lists.List.
Export Coq.Program.Program.
Global Set Implicit Arguments.
Global Coercion is_true : bool >-> Sortclass.
Coercion bool_of_sum {A B} (b : sum A B) : bool := if b then true else false.
Fixpoint ForallT {T} (P : T -> Type) (ls : list T) : Type
:= match ls return Type with
| nil => True
| x::xs => (P x * ForallT P xs)%type
end.
Fixpoint Forall_tails {T} (P : list T -> Type) (ls : list T) : Type
:= match ls with
| nil => P nil
| x::xs => (P (x::xs) * Forall_tails P xs)%type
end.
End Common.
End Fiat.
End Fiat_DOT_Common.
Module Export Fiat_DOT_Parsers_DOT_StringLike_DOT_Core.
Module Export Fiat.
Module Export Parsers.
Module Export StringLike.
Module Export Core.
Import Coq.Relations.Relation_Definitions.
Import Coq.Classes.Morphisms.
Local Coercion is_true : bool >-> Sortclass.
Module Export StringLike.
Class StringLike {Char : Type} :=
{
String :> Type;
is_char : String -> Char -> bool;
length : String -> nat;
take : nat -> String -> String;
drop : nat -> String -> String;
get : nat -> String -> option Char;
unsafe_get : nat -> String -> Char;
bool_eq : String -> String -> bool;
beq : relation String := fun x y => bool_eq x y
}.
Arguments StringLike : clear implicits.
Infix "=s" := (@beq _ _) (at level 70, no associativity) : type_scope.
Notation "s ~= [ ch ]" := (is_char s ch) (at level 70, no associativity) : string_like_scope.
Local Open Scope string_like_scope.
Class StringLikeProperties (Char : Type) `{StringLike Char} :=
{
singleton_unique : forall s ch ch', s ~= [ ch ] -> s ~= [ ch' ] -> ch = ch';
singleton_exists : forall s, length s = 1 -> exists ch, s ~= [ ch ];
get_0 : forall s ch, take 1 s ~= [ ch ] <-> get 0 s = Some ch;
get_S : forall n s, get (S n) s = get n (drop 1 s);
unsafe_get_correct : forall n s ch, get n s = Some ch -> unsafe_get n s = ch;
length_singleton : forall s ch, s ~= [ ch ] -> length s = 1;
bool_eq_char : forall s s' ch, s ~= [ ch ] -> s' ~= [ ch ] -> s =s s';
is_char_Proper :> Proper (beq ==> eq ==> eq) is_char;
length_Proper :> Proper (beq ==> eq) length;
take_Proper :> Proper (eq ==> beq ==> beq) take;
drop_Proper :> Proper (eq ==> beq ==> beq) drop;
bool_eq_Equivalence :> Equivalence beq;
bool_eq_empty : forall str str', length str = 0 -> length str' = 0 -> str =s str';
take_short_length : forall str n, n <= length str -> length (take n str) = n;
take_long : forall str n, length str <= n -> take n str =s str;
take_take : forall str n m, take n (take m str) =s take (min n m) str;
drop_length : forall str n, length (drop n str) = length str - n;
drop_0 : forall str, drop 0 str =s str;
drop_drop : forall str n m, drop n (drop m str) =s drop (n + m) str;
drop_take : forall str n m, drop n (take m str) =s take (m - n) (drop n str);
take_drop : forall str n m, take n (drop m str) =s drop m (take (n + m) str);
bool_eq_from_get : forall str str', (forall n, get n str = get n str') -> str =s str'
}.
Global Arguments StringLikeProperties _ {_}.
End StringLike.
End Core.
End StringLike.
End Parsers.
End Fiat.
End Fiat_DOT_Parsers_DOT_StringLike_DOT_Core.
Module Export Fiat_DOT_Parsers_DOT_ContextFreeGrammar_DOT_Core.
Module Export Fiat.
Module Export Parsers.
Module Export ContextFreeGrammar.
Module Export Core.
Import Coq.Strings.String.
Import Coq.Lists.List.
Export Fiat.Parsers.StringLike.Core.
Section cfg.
Context {Char : Type}.
Section definitions.
Inductive item :=
| Terminal (_ : Char)
| NonTerminal (_ : string).
Definition production := list item.
Definition productions := list production.
Record grammar :=
{
Start_symbol :> string;
Lookup :> string -> productions;
Start_productions :> productions := Lookup Start_symbol;
Valid_nonterminals : list string;
Valid_productions : list productions := map Lookup Valid_nonterminals
}.
End definitions.
End cfg.
Arguments item _ : clear implicits.
Arguments production _ : clear implicits.
Arguments productions _ : clear implicits.
Arguments grammar _ : clear implicits.
End Core.
End ContextFreeGrammar.
End Parsers.
End Fiat.
End Fiat_DOT_Parsers_DOT_ContextFreeGrammar_DOT_Core.
Module Export Fiat_DOT_Parsers_DOT_BaseTypes.
Module Export Fiat.
Module Export Parsers.
Module Export BaseTypes.
Import Coq.Arith.Wf_nat.
Local Coercion is_true : bool >-> Sortclass.
Section recursive_descent_parser.
Context {Char} {HSL : StringLike Char} {G : grammar Char}.
Class parser_computational_predataT :=
{ nonterminals_listT : Type;
nonterminal_carrierT : Type;
of_nonterminal : String.string -> nonterminal_carrierT;
to_nonterminal : nonterminal_carrierT -> String.string;
initial_nonterminals_data : nonterminals_listT;
nonterminals_length : nonterminals_listT -> nat;
is_valid_nonterminal : nonterminals_listT -> nonterminal_carrierT -> bool;
remove_nonterminal : nonterminals_listT -> nonterminal_carrierT -> nonterminals_listT }.
Class parser_removal_dataT' `{predata : parser_computational_predataT} :=
{ nonterminals_listT_R : nonterminals_listT -> nonterminals_listT -> Prop
:= ltof _ nonterminals_length;
nonterminals_length_zero : forall ls,
nonterminals_length ls = 0
-> forall nt, is_valid_nonterminal ls nt = false;
remove_nonterminal_dec : forall ls nonterminal,
is_valid_nonterminal ls nonterminal
-> nonterminals_listT_R (remove_nonterminal ls nonterminal) ls;
remove_nonterminal_noninc : forall ls nonterminal,
~nonterminals_listT_R ls (remove_nonterminal ls nonterminal);
initial_nonterminals_correct : forall nonterminal,
is_valid_nonterminal initial_nonterminals_data (of_nonterminal nonterminal) <-> List.In nonterminal (Valid_nonterminals G);
initial_nonterminals_correct' : forall nonterminal,
is_valid_nonterminal initial_nonterminals_data nonterminal <-> List.In (to_nonterminal nonterminal) (Valid_nonterminals G);
to_of_nonterminal : forall nonterminal,
List.In nonterminal (Valid_nonterminals G)
-> to_nonterminal (of_nonterminal nonterminal) = nonterminal;
of_to_nonterminal : forall nonterminal,
is_valid_nonterminal initial_nonterminals_data nonterminal
-> of_nonterminal (to_nonterminal nonterminal) = nonterminal;
ntl_wf : well_founded nonterminals_listT_R
:= well_founded_ltof _ _;
remove_nonterminal_1
: forall ls ps ps',
is_valid_nonterminal (remove_nonterminal ls ps) ps'
-> is_valid_nonterminal ls ps';
remove_nonterminal_2
: forall ls ps ps',
is_valid_nonterminal (remove_nonterminal ls ps) ps' = false
<-> is_valid_nonterminal ls ps' = false \/ ps = ps' }.
Class split_dataT :=
{ split_string_for_production
: item Char -> production Char -> String -> list nat }.
Class boolean_parser_dataT :=
{ predata :> parser_computational_predataT;
split_data :> split_dataT }.
End recursive_descent_parser.
End BaseTypes.
End Parsers.
End Fiat.
End Fiat_DOT_Parsers_DOT_BaseTypes.
Module Export Fiat_DOT_Common_DOT_List_DOT_Operations.
Module Export Fiat.
Module Export Common.
Module Export List.
Module Export Operations.
Import Coq.Lists.List.
Module Export List.
Section InT.
Context {A : Type} (a : A).
Fixpoint InT (ls : list A) : Set
:= match ls return Set with
| nil => False
| b :: m => (b = a) + InT m
end%type.
End InT.
End List.
End Operations.
End List.
End Common.
End Fiat.
End Fiat_DOT_Common_DOT_List_DOT_Operations.
Module Export Fiat_DOT_Parsers_DOT_StringLike_DOT_Properties.
Module Export Fiat.
Module Export Parsers.
Module Export StringLike.
Module Export Properties.
Section String.
Context {Char} {HSL : StringLike Char} {HSLP : StringLikeProperties Char}.
Lemma take_length {str n}
: length (take n str) = min n (length str).
admit.
Defined.
End String.
End Properties.
End StringLike.
End Parsers.
End Fiat.
End Fiat_DOT_Parsers_DOT_StringLike_DOT_Properties.
Module Export Fiat_DOT_Parsers_DOT_ContextFreeGrammar_DOT_Properties.
Module Export Fiat.
Module Export Parsers.
Module Export ContextFreeGrammar.
Module Export Properties.
Local Open Scope list_scope.
Definition production_is_reachableT {Char} (G : grammar Char) (p : production Char)
:= { nt : _
& { prefix : _
& List.In nt (Valid_nonterminals G)
* List.InT
(prefix ++ p)
(Lookup G nt) } }%type.
End Properties.
End ContextFreeGrammar.
End Parsers.
End Fiat.
End Fiat_DOT_Parsers_DOT_ContextFreeGrammar_DOT_Properties.
Module Export Fiat_DOT_Parsers_DOT_MinimalParse.
Module Export Fiat.
Module Export Parsers.
Module Export MinimalParse.
Import Coq.Lists.List.
Import Fiat.Parsers.ContextFreeGrammar.Core.
Local Coercion is_true : bool >-> Sortclass.
Local Open Scope string_like_scope.
Section cfg.
Context {Char} {HSL : StringLike Char} {G : grammar Char}.
Context {predata : @parser_computational_predataT}
{rdata' : @parser_removal_dataT' _ G predata}.
Inductive minimal_parse_of
: forall (len0 : nat) (valid : nonterminals_listT)
(str : String),
productions Char -> Type :=
| MinParseHead : forall len0 valid str pat pats,
@minimal_parse_of_production len0 valid str pat
-> @minimal_parse_of len0 valid str (pat::pats)
| MinParseTail : forall len0 valid str pat pats,
@minimal_parse_of len0 valid str pats
-> @minimal_parse_of len0 valid str (pat::pats)
with minimal_parse_of_production
: forall (len0 : nat) (valid : nonterminals_listT)
(str : String),
production Char -> Type :=
| MinParseProductionNil : forall len0 valid str,
length str = 0
-> @minimal_parse_of_production len0 valid str nil
| MinParseProductionCons : forall len0 valid str n pat pats,
length str <= len0
-> @minimal_parse_of_item len0 valid (take n str) pat
-> @minimal_parse_of_production len0 valid (drop n str) pats
-> @minimal_parse_of_production len0 valid str (pat::pats)
with minimal_parse_of_item
: forall (len0 : nat) (valid : nonterminals_listT)
(str : String),
item Char -> Type :=
| MinParseTerminal : forall len0 valid str ch,
str ~= [ ch ]
-> @minimal_parse_of_item len0 valid str (Terminal ch)
| MinParseNonTerminal
: forall len0 valid str (nt : String.string),
@minimal_parse_of_nonterminal len0 valid str nt
-> @minimal_parse_of_item len0 valid str (NonTerminal nt)
with minimal_parse_of_nonterminal
: forall (len0 : nat) (valid : nonterminals_listT)
(str : String),
String.string -> Type :=
| MinParseNonTerminalStrLt
: forall len0 valid (nt : String.string) str,
length str < len0
-> is_valid_nonterminal initial_nonterminals_data (of_nonterminal nt)
-> @minimal_parse_of (length str) initial_nonterminals_data str (Lookup G nt)
-> @minimal_parse_of_nonterminal len0 valid str nt
| MinParseNonTerminalStrEq
: forall len0 str valid nonterminal,
length str = len0
-> is_valid_nonterminal initial_nonterminals_data (of_nonterminal nonterminal)
-> is_valid_nonterminal valid (of_nonterminal nonterminal)
-> @minimal_parse_of len0 (remove_nonterminal valid (of_nonterminal nonterminal)) str (Lookup G nonterminal)
-> @minimal_parse_of_nonterminal len0 valid str nonterminal.
End cfg.
End MinimalParse.
End Parsers.
End Fiat.
End Fiat_DOT_Parsers_DOT_MinimalParse.
Module Export Fiat_DOT_Parsers_DOT_CorrectnessBaseTypes.
Module Export Fiat.
Module Export Parsers.
Module Export CorrectnessBaseTypes.
Import Coq.Lists.List.
Import Fiat.Parsers.ContextFreeGrammar.Core.
Import Fiat_DOT_Common.Fiat.Common.
Section general.
Context {Char} {HSL : StringLike Char} {G : grammar Char}.
Definition split_list_completeT_for {data : @parser_computational_predataT}
{len0 valid}
(it : item Char) (its : production Char)
(str : String)
(pf : length str <= len0)
(split_list : list nat)
:= ({ n : nat
& (minimal_parse_of_item (G := G) (predata := data) len0 valid (take n str) it)
* (minimal_parse_of_production (G := G) len0 valid (drop n str) its) }%type)
-> ({ n : nat
& (In (min (length str) n) (map (min (length str)) split_list))
* (minimal_parse_of_item (G := G) len0 valid (take n str) it)
* (minimal_parse_of_production (G := G) len0 valid (drop n str) its) }%type).
Definition split_list_completeT {data : @parser_computational_predataT}
(splits : item Char -> production Char -> String -> list nat)
:= forall len0 valid str (pf : length str <= len0) nt,
is_valid_nonterminal initial_nonterminals_data (of_nonterminal nt)
-> ForallT
(Forall_tails
(fun prod
=> match prod return Type with
| nil => True
| it::its
=> @split_list_completeT_for data len0 valid it its str pf (splits it its str)
end))
(Lookup G nt).
Class boolean_parser_completeness_dataT' {data : boolean_parser_dataT} :=
{ split_string_for_production_complete
: split_list_completeT split_string_for_production }.
End general.
End CorrectnessBaseTypes.
End Parsers.
End Fiat.
End Fiat_DOT_Parsers_DOT_CorrectnessBaseTypes.
Module Export Fiat.
Module Export Parsers.
Module Export ContextFreeGrammar.
Module Export Valid.
Export Fiat.Parsers.StringLike.Core.
Section cfg.
Context {Char : Type} {HSL : StringLike Char} (G : grammar Char)
{predata : parser_computational_predataT}.
Definition item_valid (it : item Char)
:= match it with
| Terminal _ => True
| NonTerminal nt' => is_true (is_valid_nonterminal initial_nonterminals_data (of_nonterminal nt'))
end.
Definition production_valid pat
:= List.Forall item_valid pat.
Definition productions_valid pats
:= List.Forall production_valid pats.
Definition grammar_valid
:= forall nt,
List.In nt (Valid_nonterminals G)
-> productions_valid (Lookup G nt).
End cfg.
End Valid.
Section app.
Context {Char : Type} {HSL : StringLike Char} (G : grammar Char)
{predata : parser_computational_predataT}.
Lemma hd_production_valid
(it : item Char)
(its : production Char)
(H : production_valid (it :: its))
: item_valid it.
admit.
Defined.
Lemma production_valid_cons
(it : item Char)
(its : production Char)
(H : production_valid (it :: its))
: production_valid its.
admit.
Defined.
End app.
Import Coq.Lists.List.
Import Coq.omega.Omega.
Import Fiat_DOT_Common.Fiat.Common.
Import Fiat.Parsers.ContextFreeGrammar.Valid.
Local Open Scope string_like_scope.
Section recursive_descent_parser.
Context {Char} {HSL : StringLike Char} {HSLP : StringLikeProperties Char} (G : grammar Char).
Context {data : @boolean_parser_dataT Char _}
{cdata : @boolean_parser_completeness_dataT' Char _ G data}
{rdata : @parser_removal_dataT' _ G _}
{gvalid : grammar_valid G}.
Local Notation dec T := (T + (T -> False))%type (only parsing).
Local Notation iffT x y := ((x -> y) * (y -> x))%type (only parsing).
Lemma dec_prod {A B} (HA : dec A) (HB : dec B) : dec (A * B).
admit.
Defined.
Lemma dec_In {A} {P : A -> Type} (HA : forall a, dec (P a)) ls
: dec { a : _ & (In a ls * P a) }.
admit.
Defined.
Section item.
Context {len0 valid}
(str : String)
(str_matches_nonterminal'
: nonterminal_carrierT -> bool)
(str_matches_nonterminal
: forall nt : nonterminal_carrierT,
dec (minimal_parse_of_nonterminal (G := G) len0 valid str (to_nonterminal nt))).
Section valid.
Context (Hmatches
: forall nt,
is_valid_nonterminal initial_nonterminals_data nt
-> str_matches_nonterminal nt = str_matches_nonterminal' nt :> bool)
(it : item Char)
(Hvalid : item_valid it).
Definition parse_item'
: dec (minimal_parse_of_item (G := G) len0 valid str it).
Proof.
clear Hvalid.
refine (match it return dec (minimal_parse_of_item len0 valid str it) with
| Terminal ch => if Sumbool.sumbool_of_bool (str ~= [ ch ])
then inl (MinParseTerminal _ _ _ _ _)
else inr (fun _ => !)
| NonTerminal nt => if str_matches_nonterminal (of_nonterminal nt)
then inl (MinParseNonTerminal _)
else inr (fun _ => !)
end);
clear str_matches_nonterminal Hmatches;
admit.
Defined.
End valid.
End item.
Context {len0 valid}
(parse_nonterminal
: forall (str : String) (len : nat) (Hlen : length str = len) (pf : len <= len0) (nt : nonterminal_carrierT),
dec (minimal_parse_of_nonterminal (G := G) len0 valid str (to_nonterminal nt))).
Lemma dec_in_helper {ls it its str}
: iffT {n0 : nat &
(In (min (length str) n0) (map (min (length str)) ls) *
minimal_parse_of_item (G := G) len0 valid (take n0 str) it *
minimal_parse_of_production (G := G) len0 valid (drop n0 str) its)%type}
{n0 : nat &
(In n0 ls *
(minimal_parse_of_item (G := G) len0 valid (take n0 str) it *
minimal_parse_of_production (G := G) len0 valid (drop n0 str) its))%type}.
admit.
Defined.
Lemma parse_production'_helper {str it its} (pf : length str <= len0)
: dec {n0 : nat &
(minimal_parse_of_item (G := G) len0 valid (take n0 str) it *
minimal_parse_of_production (G := G) len0 valid (drop n0 str) its)%type}
-> dec (minimal_parse_of_production (G := G) len0 valid str (it :: its)).
admit.
Defined.
Local Ltac t_parse_production_for := repeat
match goal with
| [ H : (beq_nat _ _) = true |- _ ] => apply EqNat.beq_nat_true in H
| _ => progress subst
| _ => solve [ constructor; assumption ]
| [ H : minimal_parse_of_production _ _ _ nil |- _ ] => (inversion H; clear H)
| [ H : minimal_parse_of_production _ _ _ (_::_) |- _ ] => (inversion H; clear H)
| [ H : ?x = 0, H' : context[?x] |- _ ] => rewrite H in H'
| _ => progress simpl in *
| _ => discriminate
| [ H : forall x, (_ * _)%type -> _ |- _ ] => specialize (fun x y z => H x (y, z))
| _ => solve [ eauto with nocore ]
| _ => solve [ apply Min.min_case_strong; omega ]
| _ => omega
| [ H : production_valid (_::_) |- _ ]
=> let H' := fresh in
pose proof H as H';
apply production_valid_cons in H;
apply hd_production_valid in H'
end.
Definition parse_production'_for
(splits : item Char -> production Char -> String -> list nat)
(Hsplits : forall str it its (Hreachable : production_is_reachableT G (it::its)) pf', split_list_completeT_for (len0 := len0) (G := G) (valid := valid) it its str pf' (splits it its str))
(str : String)
(len : nat)
(Hlen : length str = len)
(pf : len <= len0)
(prod : production Char)
(Hreachable : production_is_reachableT G prod)
: dec (minimal_parse_of_production (G := G) len0 valid str prod).
Proof.
revert prod Hreachable str len Hlen pf.
refine
((fun pf_helper =>
list_rect
(fun prod =>
forall (Hreachable : production_is_reachableT G prod)
(str : String)
(len : nat)
(Hlen : length str = len)
(pf : len <= len0),
dec (minimal_parse_of_production (G := G) len0 valid str prod))
(
fun Hreachable str len Hlen pf
=> match Utils.dec (beq_nat len 0) with
| left H => inl _
| right H => inr (fun p => _)
end)
(fun it its parse_production' Hreachable str len Hlen pf
=> parse_production'_helper
_
(let parse_item := (fun n pf => parse_item' (parse_nonterminal (take n str) (len := min n len) (eq_trans take_length (f_equal (min _) Hlen)) pf) it) in
let parse_item := (fun n => parse_item n (Min.min_case_strong n len (fun k => k <= len0) (fun Hlen => (Nat.le_trans _ _ _ Hlen pf)) (fun Hlen => pf))) in
let parse_production := (fun n => parse_production' (pf_helper it its Hreachable) (drop n str) (len - n) (eq_trans (drop_length _ _) (f_equal (fun x => x - _) Hlen)) (Nat.le_trans _ _ _ (Nat.le_sub_l _ _) pf)) in
match dec_In
(fun n => dec_prod (parse_item n) (parse_production n))
(splits it its str)
with
| inl p => inl (existT _ (projT1 p) (snd (projT2 p)))
| inr p
=> let pf' := (Nat.le_trans _ _ _ (Nat.eq_le_incl _ _ Hlen) pf) in
let H := (_ : split_list_completeT_for (G := G) (len0 := len0) (valid := valid) it its str pf' (splits it its str)) in
inr (fun p' => p (fst dec_in_helper (H p')))
end)
)) _);
[ clear parse_nonterminal Hsplits splits rdata cdata
| clear parse_nonterminal Hsplits splits rdata cdata
| ..
| admit ].
abstract t_parse_production_for.
abstract t_parse_production_for.
abstract t_parse_production_for.
abstract t_parse_production_for.
Defined.
|