%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2008-2011. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
%% compliance with the License. You should have received a copy of the
%% Erlang Public License along with this software. If not, it can be
%% retrieved online at http://www.erlang.org/.
%%
%% Software distributed under the License is distributed on an "AS IS"
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
%% the License for the specific language governing rights and limitations
%% under the License.
%%
%% %CopyrightEnd%
%%
-module(re).
-export([grun/3,urun/3,ucompile/2,replace/3,replace/4,split/2,split/3]).
%-opaque mp() :: {re_pattern, _, _, _}.
-type mp() :: {re_pattern, _, _, _}.
-type nl_spec() :: cr | crlf | lf | anycrlf | any.
-type compile_option() :: unicode | anchored | caseless | dollar_endonly
| dotall | extended | firstline | multiline
| no_auto_capture | dupnames | ungreedy
| {newline, nl_spec()}| bsr_anycrlf
| bsr_unicode.
%% Emulator builtins in this module:
%% re:compile/1
%% re:compile/2
%% re:run/2
%% re:run/3
-spec split(Subject, RE) -> SplitList when
Subject :: iodata() | unicode:charlist(),
RE :: mp() | iodata(),
SplitList :: [iodata() | unicode:charlist()].
split(Subject,RE) ->
split(Subject,RE,[]).
-spec split(Subject, RE, Options) -> SplitList when
Subject :: iodata() | unicode:charlist(),
RE :: mp() | iodata() | unicode:charlist(),
Options :: [ Option ],
Option :: anchored | global | notbol | noteol | notempty
| {offset, non_neg_integer()} | {newline, nl_spec()}
| bsr_anycrlf | bsr_unicode | {return, ReturnType}
| {parts, NumParts} | group | trim | CompileOpt,
NumParts :: non_neg_integer() | infinity,
ReturnType :: iodata | list | binary,
CompileOpt :: compile_option(),
SplitList :: [RetData] | [GroupedRetData],
GroupedRetData :: [RetData],
RetData :: iodata() | unicode:charlist() | binary() | list().
split(Subject,RE,Options) ->
try
{NewOpt,Convert,Unicode,Limit,Strip,Group} =
process_split_params(Options,iodata,false,-1,false,false),
FlatSubject = to_binary(Subject, Unicode),
case compile_split(RE,NewOpt) of
{error,_Err} ->
throw(badre);
{PreCompiled, NumSub, RunOpt} ->
%% OK, lets run
case re:run(FlatSubject,PreCompiled,RunOpt ++ [global]) of
nomatch ->
case Group of
true ->
convert_any_split_result([[FlatSubject]],
Convert, Unicode, true);
false ->
convert_any_split_result([FlatSubject],
Convert, Unicode, false)
end;
{match, Matches} ->
Res = do_split(FlatSubject, 0, Matches, NumSub,
Limit, Group),
Stripped = case Strip of
true ->
backstrip_empty(Res,Group);
false ->
Res
end,
convert_any_split_result(Stripped, Convert, Unicode, Group)
end
end
catch
throw:badopt ->
erlang:error(badarg,[Subject,RE,Options]);
throw:badre ->
erlang:error(badarg,[Subject,RE,Options]);
error:badarg ->
erlang:error(badarg,[Subject,RE,Options])
end.
backstrip_empty(List, false) ->
do_backstrip_empty(List);
backstrip_empty(List, true) ->
do_backstrip_empty_g(List).
do_backstrip_empty_g([]) ->
[];
do_backstrip_empty_g([H]) ->
case do_backstrip_empty(H) of
[] ->
[];
_ ->
[H]
end;
do_backstrip_empty_g([H|T]) ->
case do_backstrip_empty_g(T) of
[] ->
case do_backstrip_empty(H) of
[] ->
[];
_ ->
[H]
end;
Other ->
[H|Other]
end.
do_backstrip_empty([]) ->
[];
do_backstrip_empty([<<>>]) ->
[];
do_backstrip_empty([<<>>|T]) ->
case do_backstrip_empty(T) of
[] ->
[];
Other ->
[<<>>|Other]
end;
do_backstrip_empty([H|T]) ->
[H|do_backstrip_empty(T)].
convert_any_split_result(List,Type,Uni,true) ->
[ convert_split_result(Part,Type,Uni) || Part <- List ];
convert_any_split_result(List,Type,Uni, false) ->
convert_split_result(List,Type,Uni).
convert_split_result(List, iodata, _Unicode) ->
List;
convert_split_result(List, binary, _Unicode) ->
%% As it happens, the iodata is actually binaries
List;
convert_split_result(List, list, true) ->
[unicode:characters_to_list(Element,unicode) || Element <- List];
convert_split_result(List, list, false) ->
[binary_to_list(Element) || Element <- List].
do_split(Subj, Off, _, _, 0, false) ->
<<_:Off/binary,Rest/binary>> = Subj,
[Rest];
do_split(Subj, Off, [], _, _, false) ->
<<_:Off/binary,Rest/binary>> = Subj,
[Rest];
do_split(Subj, Off, _, _, _,false) when byte_size(Subj) =< Off ->
[<<>>];
do_split(Subj, Off, _, _, 0, true) ->
<<_:Off/binary,Rest/binary>> = Subj,
[[Rest]];
do_split(Subj, Off, [], _, _, true) ->
<<_:Off/binary,Rest/binary>> = Subj,
[[Rest]];
do_split(Subj, Off, _, _, _,true) when byte_size(Subj) =< Off ->
[[<<>>]];
do_split(Subj, Offset, [[{MainI,MainL}|Sub]|T], NumSub, Limit, Group) ->
NewOffset = MainI+MainL,
KeptLen = MainI - Offset,
case {KeptLen,empty_sub(Sub),MainL} of
{0,true,0} ->
do_split(Subj,NewOffset,T,NumSub,Limit,Group);
_ ->
<<_:Offset/binary,Keep:KeptLen/binary,_/binary>> = Subj,
ESub = extend_subpatterns(Sub,NumSub),
Tail = do_split(Subj, NewOffset, T, NumSub, Limit - 1,Group),
case Group of
false ->
[Keep | dig_subpatterns(Subj,lists:reverse(ESub),Tail)];
true ->
[[Keep | dig_subpatterns(Subj,lists:reverse(ESub),[])]|
Tail]
end
end.
empty_sub([]) ->
true;
empty_sub([{_,0}|T]) ->
empty_sub(T);
empty_sub(_) ->
false.
dig_subpatterns(_,[],Acc) ->
Acc;
dig_subpatterns(Subj,[{-1,0}|T],Acc) ->
dig_subpatterns(Subj,T,[<<>>|Acc]);
dig_subpatterns(Subj,[{I,L}|T],Acc) ->
<<_:I/binary,Part:L/binary,_/binary>> = Subj,
dig_subpatterns(Subj,T,[Part|Acc]).
extend_subpatterns(_,0) ->
[];
extend_subpatterns([],N) ->
[{0,0} | extend_subpatterns([],N-1)];
extend_subpatterns([H|T],N) ->
[H | extend_subpatterns(T,N-1)].
compile_split({re_pattern,N,_,_} = Comp, Options) ->
{Comp,N,Options};
compile_split(Pat,Options0) when not is_tuple(Pat) ->
Options = lists:filter(fun(O) ->
(not runopt(O))
end, Options0),
case re:compile(Pat,Options) of
{error,Err} ->
{error,Err};
{ok, {re_pattern,N,_,_} = Comp} ->
NewOpt = lists:filter(fun(OO) -> (not copt(OO)) end, Options0),
{Comp,N,NewOpt}
end;
compile_split(_,_) ->
throw(badre).
-spec replace(Subject, RE, Replacement) -> iodata() | unicode:charlist() when
Subject :: iodata() | unicode:charlist(),
RE :: mp() | iodata(),
Replacement :: iodata() | unicode:charlist().
replace(Subject,RE,Replacement) ->
replace(Subject,RE,Replacement,[]).
-spec replace(Subject, RE, Replacement, Options) -> iodata() | unicode:charlist() when
Subject :: iodata() | unicode:charlist(),
RE :: mp() | iodata() | unicode:charlist(),
Replacement :: iodata() | unicode:charlist(),
Options :: [Option],
Option :: anchored | global | notbol | noteol | notempty
| {offset, non_neg_integer()} | {newline, NLSpec} | bsr_anycrlf
| bsr_unicode | {return, ReturnType} | CompileOpt,
ReturnType :: iodata | list | binary,
CompileOpt :: compile_option(),
NLSpec :: cr | crlf | lf | anycrlf | any.
replace(Subject,RE,Replacement,Options) ->
try
{NewOpt,Convert,Unicode} =
process_repl_params(Options,iodata,false),
FlatSubject = to_binary(Subject, Unicode),
FlatReplacement = to_binary(Replacement, Unicode),
IoList = do_replace(FlatSubject,Subject,RE,FlatReplacement,NewOpt),
case Convert of
iodata ->
IoList;
binary ->
case Unicode of
false ->
iolist_to_binary(IoList);
true ->
unicode:characters_to_binary(IoList,unicode)
end;
list ->
case Unicode of
false ->
binary_to_list(iolist_to_binary(IoList));
true ->
unicode:characters_to_list(IoList,unicode)
end
end
catch
throw:badopt ->
erlang:error(badarg,[Subject,RE,Replacement,Options]);
throw:badre ->
erlang:error(badarg,[Subject,RE,Replacement,Options]);
error:badarg ->
erlang:error(badarg,[Subject,RE,Replacement,Options])
end.
do_replace(FlatSubject,Subject,RE,Replacement,Options) ->
case re:run(FlatSubject,RE,Options) of
nomatch ->
Subject;
{match,[Mlist|T]} when is_list(Mlist) ->
apply_mlist(FlatSubject,Replacement,[Mlist|T]);
{match,Slist} ->
apply_mlist(FlatSubject,Replacement,[Slist])
end.
process_repl_params([],Convert,Unicode) ->
{[],Convert,Unicode};
process_repl_params([unicode|T],C,_U) ->
{NT,NC,NU} = process_repl_params(T,C,true),
{[unicode|NT],NC,NU};
process_repl_params([{capture,_,_}|_],_,_) ->
throw(badopt);
process_repl_params([{capture,_}|_],_,_) ->
throw(badopt);
process_repl_params([{return,iodata}|T],_C,U) ->
process_repl_params(T,iodata,U);
process_repl_params([{return,list}|T],_C,U) ->
process_repl_params(T,list,U);
process_repl_params([{return,binary}|T],_C,U) ->
process_repl_params(T,binary,U);
process_repl_params([{return,_}|_],_,_) ->
throw(badopt);
process_repl_params([H|T],C,U) ->
{NT,NC,NU} = process_repl_params(T,C,U),
{[H|NT],NC,NU}.
process_split_params([],Convert,Unicode,Limit,Strip,Group) ->
{[],Convert,Unicode,Limit,Strip,Group};
process_split_params([unicode|T],C,_U,L,S,G) ->
{NT,NC,NU,NL,NS,NG} = process_split_params(T,C,true,L,S,G),
{[unicode|NT],NC,NU,NL,NS,NG};
process_split_params([trim|T],C,U,_L,_S,G) ->
process_split_params(T,C,U,-1,true,G);
process_split_params([{parts,0}|T],C,U,_L,_S,G) ->
process_split_params(T,C,U,-1,true,G);
process_split_params([{parts,N}|T],C,U,_L,_S,G) when is_integer(N), N >= 1 ->
process_split_params(T,C,U,N-1,false,G);
process_split_params([{parts,infinity}|T],C,U,_L,_S,G) ->
process_split_params(T,C,U,-1,false,G);
process_split_params([{parts,_}|_],_,_,_,_,_) ->
throw(badopt);
process_split_params([group|T],C,U,L,S,_G) ->
process_split_params(T,C,U,L,S,true);
process_split_params([global|_],_,_,_,_,_) ->
throw(badopt);
process_split_params([{capture,_,_}|_],_,_,_,_,_) ->
throw(badopt);
process_split_params([{capture,_}|_],_,_,_,_,_) ->
throw(badopt);
process_split_params([{return,iodata}|T],_C,U,L,S,G) ->
process_split_params(T,iodata,U,L,S,G);
process_split_params([{return,list}|T],_C,U,L,S,G) ->
process_split_params(T,list,U,L,S,G);
process_split_params([{return,binary}|T],_C,U,L,S,G) ->
process_split_params(T,binary,U,L,S,G);
process_split_params([{return,_}|_],_,_,_,_,_) ->
throw(badopt);
process_split_params([H|T],C,U,L,S,G) ->
{NT,NC,NU,NL,NS,NG} = process_split_params(T,C,U,L,S,G),
{[H|NT],NC,NU,NL,NS,NG}.
apply_mlist(Subject,Replacement,Mlist) ->
do_mlist(Subject,Subject,0,precomp_repl(Replacement), Mlist).
precomp_repl(<<>>) ->
[];
precomp_repl(<<$\\,X,Rest/binary>>) when X < $1 ; X > $9 ->
%% Escaped character
case precomp_repl(Rest) of
[BHead | T0] when is_binary(BHead) ->
[<<X,BHead/binary>> | T0];
Other ->
[<<X>> | Other]
end;
precomp_repl(<<$\\,Rest/binary>>) when byte_size(Rest) > 0->
{NS,NRest} = pick_int(Rest),
[list_to_integer(NS) | precomp_repl(NRest)];
precomp_repl(<<$&,Rest/binary>>) ->
[0 | precomp_repl(Rest)];
precomp_repl(<<X,Rest/binary>>) ->
case precomp_repl(Rest) of
[BHead | T0] when is_binary(BHead) ->
[<<X,BHead/binary>> | T0];
Other ->
[<<X>> | Other]
end.
pick_int(<<X,R/binary>>) when X >= $0, X =< $9 ->
{Found,Rest} = pick_int(R),
{[X|Found],Rest};
pick_int(Bin) ->
{[],Bin}.
do_mlist(_,<<>>,_,_,[]) ->
[]; %Avoid empty binary tail
do_mlist(_,Subject,_,_,[]) ->
Subject;
do_mlist(Whole,Subject,Pos,Repl,[[{MPos,Count} | Sub] | Tail])
when MPos > Pos ->
EatLength = MPos - Pos,
<<Untouched:EatLength/binary, Rest/binary>> = Subject,
[Untouched | do_mlist(Whole,Rest, MPos, Repl,
[[{MPos,Count} | Sub] | Tail])];
do_mlist(Whole,Subject,Pos,Repl,[[{MPos,Count} | Sub] | Tail])
when MPos =:= Pos ->
EatLength = Count,
<<_:EatLength/binary,Rest/binary>> = Subject,
NewData = do_replace(Whole,Repl,[{MPos,Count} | Sub]),
[NewData | do_mlist(Whole,Rest,Pos+EatLength,Repl,Tail)].
do_replace(_,[Bin],_) when is_binary(Bin) ->
Bin;
do_replace(Subject,Repl,SubExprs0) ->
SubExprs = list_to_tuple(SubExprs0),
[ case Part of
N when is_integer(N) ->
if
tuple_size(SubExprs) =< N ->
<<>>;
true ->
{SPos,SLen} = element(N+1,SubExprs),
if
SPos < 0 ->
<<>>;
true ->
<<_:SPos/binary,Res:SLen/binary,_/binary>> =
Subject,
Res
end
end;
Other ->
Other
end || Part <- Repl ].
check_for_unicode({re_pattern,_,1,_},_) ->
true;
check_for_unicode({re_pattern,_,0,_},_) ->
false;
check_for_unicode(_,L) ->
lists:member(unicode,L).
% SelectReturn = false | all | stirpfirst | none
% ConvertReturn = index | list | binary
% {capture, all} -> all (untouchded)
% {capture, first} -> kept in argumentt list and Select all
% {capture, all_but_first} -> removed from argument list and selects stripfirst
% {capture, none} -> removed from argument list and selects none
% {capture, []} -> removed from argument list and selects none
% {capture,[...]} -> 0 added to selection list and selects stripfirst
% SelectReturn false is same as all in the end.
% Call as process_parameters([],0,false,index,NeedClean)
process_parameters([],InitialOffset, SelectReturn, ConvertReturn,_) ->
{[], InitialOffset, SelectReturn, ConvertReturn};
process_parameters([{offset, N} | T],_Init0,Select0,Return0,CC) ->
process_parameters(T,N,Select0,Return0,CC);
process_parameters([global | T],Init0,Select0,Return0,CC) ->
process_parameters(T,Init0,Select0,Return0,CC);
process_parameters([{capture,Values,Type}|T],Init0,Select0,_Return0,CC) ->
process_parameters([{capture,Values}|T],Init0,Select0,Type,CC);
process_parameters([{capture,Values}|T],Init0,Select0,Return0,CC) ->
% First process the rest to see if capture was already present
{NewTail, Init1, Select1, Return1} =
process_parameters(T,Init0,Select0,Return0,CC),
case Select1 of
false ->
case Values of
all ->
{[{capture,all} | NewTail], Init1, all, Return0};
first ->
{[{capture,first} | NewTail], Init1, all, Return0};
all_but_first ->
{[{capture,all} | NewTail], Init1, stripfirst, Return0};
none ->
{[{capture,first} | NewTail], Init1, none, Return0};
[] ->
{[{capture,first} | NewTail], Init1, none, Return0};
List when is_list(List) ->
{[{capture,[0|List]} | NewTail],
Init1, stripfirst, Return0};
_ ->
throw(badlist)
end;
_ ->
% Found overriding further down list, ignore this one
{NewTail, Init1, Select1, Return1}
end;
process_parameters([H|T],Init0,Select0,Return0,true) ->
case copt(H) of
true ->
process_parameters(T,Init0,Select0,Return0,true);
false ->
{NewT,Init,Select,Return} =
process_parameters(T,Init0,Select0,Return0,true),
{[H|NewT],Init,Select,Return}
end;
process_parameters([H|T],Init0,Select0,Return0,false) ->
{NewT,Init,Select,Return} =
process_parameters(T,Init0,Select0,Return0,false),
{[H|NewT],Init,Select,Return};
process_parameters(_,_,_,_,_) ->
throw(badlist).
postprocess({match,[]},_,_,_,_) ->
nomatch;
postprocess({match,_},none,_,_,_) ->
match;
postprocess({match,M},Any,binary,Flat,Uni) ->
binarify(postprocess({match,M},Any,index,Flat,Uni),Flat);
postprocess({match,M},Any,list,Flat,Uni) ->
listify(postprocess({match,M},Any,index,Flat,Uni),Flat,Uni);
postprocess({match,M},all,index,_,_) ->
{match,M};
postprocess({match,M},false,index,_,_) ->
{match,M};
postprocess({match,M},stripfirst,index,_,_) ->
{match, [ T || [_|T] <- M ]}.
binarify({match,M},Flat) ->
{match, [ [ case {I,L} of
{-1,0} ->
<<>>;
{SPos,SLen} ->
<<_:SPos/binary,Res:SLen/binary,_/binary>> = Flat,
Res
end || {I,L} <- One ] || One <- M ]}.
listify({match,M},Flat,Uni) ->
{match, [ [ case {I,L} of
{_,0} ->
[];
{SPos,SLen} ->
case Uni of
true ->
<<_:SPos/binary,Res:SLen/binary,_/binary>> = Flat,
unicode:characters_to_list(Res,unicode);
false ->
Start = SPos + 1,
End = SPos + SLen,
binary_to_list(Flat,Start,End)
end
end || {I,L} <- One ] || One <- M ]}.
ubinarify({match,M},Flat) ->
{match, [ case {I,L} of
{-1,0} ->
<<>>;
{SPos,SLen} ->
<<_:SPos/binary,Res:SLen/binary,_/binary>> = Flat,
Res
end || {I,L} <- M ]};
ubinarify(Else,_) ->
Else.
ulistify({match,M},Flat) ->
{match, [ case {I,L} of
{_,0} ->
[];
{SPos,SLen} ->
<<_:SPos/binary,Res:SLen/binary,_/binary>> = Flat,
unicode:characters_to_list(Res,unicode)
end || {I,L} <- M ]};
ulistify(Else,_) ->
Else.
process_uparams([global|_T],_RetType) ->
throw(false);
process_uparams([{capture,Values,Type}|T],_OldType) ->
process_uparams([{capture,Values}|T],Type);
process_uparams([H|T],Type) ->
{NL,NType} = process_uparams(T,Type),
{[H|NL],NType};
process_uparams([],Type) ->
{[],Type}.
ucompile(RE,Options) ->
try
re:compile(unicode:characters_to_binary(RE,unicode),Options)
catch
error:AnyError ->
{'EXIT',{new_stacktrace,[{Mod,_,L}|Rest]}} =
(catch erlang:error(new_stacktrace,
[RE,Options])),
erlang:raise(error,AnyError,[{Mod,compile,L}|Rest])
end.
urun(Subject,RE,Options) ->
try
urun2(Subject,RE,Options)
catch
error:AnyError ->
{'EXIT',{new_stacktrace,[{Mod,_,L}|Rest]}} =
(catch erlang:error(new_stacktrace,
[Subject,RE,Options])),
erlang:raise(error,AnyError,[{Mod,run,L}|Rest])
end.
urun2(Subject0,RE0,Options0) ->
{Options,RetType} = case (catch process_uparams(Options0,index)) of
{A,B} ->
{A,B};
_ ->
{Options0,false}
end,
Subject = unicode:characters_to_binary(Subject0,unicode),
RE = case RE0 of
BinRE when is_binary(BinRE) ->
BinRE;
{re_pattern,_,_,_} = ReCompiled ->
ReCompiled;
ListRE ->
unicode:characters_to_binary(ListRE,unicode)
end,
Ret = re:run(Subject,RE,Options),
case RetType of
binary ->
ubinarify(Ret,Subject);
list ->
ulistify(Ret,Subject);
_ ->
Ret
end.
%% Might be called either with two-tuple (if regexp was already compiled)
%% or with 3-tuple (saving original RE for exceptions
grun(Subject,RE,{Options,NeedClean}) ->
try
grun2(Subject,RE,{Options,NeedClean})
catch
error:AnyError ->
{'EXIT',{new_stacktrace,[{Mod,_,L}|Rest]}} =
(catch erlang:error(new_stacktrace,
[Subject,RE,Options])),
erlang:raise(error,AnyError,[{Mod,run,L}|Rest])
end;
grun(Subject,RE,{Options,NeedClean,OrigRE}) ->
try
grun2(Subject,RE,{Options,NeedClean})
catch
error:AnyError ->
{'EXIT',{new_stacktrace,[{Mod,_,L}|Rest]}} =
(catch erlang:error(new_stacktrace,
[Subject,OrigRE,Options])),
erlang:raise(error,AnyError,[{Mod,run,L}|Rest])
end.
grun2(Subject,RE,{Options,NeedClean}) ->
Unicode = check_for_unicode(RE,Options),
FlatSubject = to_binary(Subject, Unicode),
do_grun(FlatSubject,Subject,Unicode,RE,{Options,NeedClean}).
do_grun(FlatSubject,Subject,Unicode,RE,{Options0,NeedClean}) ->
{StrippedOptions, InitialOffset,
SelectReturn, ConvertReturn} =
case (catch
process_parameters(Options0, 0, false, index, NeedClean)) of
badlist ->
erlang:error(badarg,[Subject,RE,Options0]);
CorrectReturn ->
CorrectReturn
end,
postprocess(loopexec(FlatSubject,RE,InitialOffset,
byte_size(FlatSubject),
Unicode,StrippedOptions),
SelectReturn,ConvertReturn,FlatSubject,Unicode).
loopexec(_,_,X,Y,_,_) when X > Y ->
{match,[]};
loopexec(Subject,RE,X,Y,Unicode,Options) ->
case re:run(Subject,RE,[{offset,X}]++Options) of
nomatch ->
{match,[]};
{match,[{A,B}|More]} ->
{match,Rest} =
case B>0 of
true ->
loopexec(Subject,RE,A+B,Y,Unicode,Options);
false ->
{match,M} =
case re:run(Subject,RE,[{offset,X},notempty,
anchored]++Options) of
nomatch ->
{match,[]};
{match,Other} ->
{match,Other}
end,
NewA = case M of
[{_,NStep}|_] when NStep > 0 ->
A+NStep;
_ ->
forward(Subject,A,1,Unicode)
end,
{match,MM} = loopexec(Subject,RE,NewA,Y,
Unicode,Options),
case M of
[] ->
{match,MM};
_ ->
{match,[M | MM]}
end
end,
{match,[[{A,B}|More] | Rest]}
end.
forward(_Chal,A,0,_) ->
A;
forward(_Chal,A,N,false) ->
A+N;
forward(Chal,A,N,true) ->
<<_:A/binary,Tl/binary>> = Chal,
Forw = case Tl of
<<1:1,1:1,0:1,_:5,_/binary>> ->
2;
<<1:1,1:1,1:1,0:1,_:4,_/binary>> ->
3;
<<1:1,1:1,1:1,1:1,0:1,_:3,_/binary>> ->
4;
_ ->
1
end,
forward(Chal,A+Forw,N-1,true).
copt(caseless) ->
true;
copt(dollar_endonly) ->
true;
copt(dotall) ->
true;
copt(extended) ->
true;
copt(firstline) ->
true;
copt(multiline) ->
true;
copt(no_auto_capture) ->
true;
copt(dupnames) ->
true;
copt(ungreedy) ->
true;
copt(unicode) ->
true;
copt(_) ->
false.
%bothopt({newline,_}) ->
% true;
%bothopt(anchored) ->
% true;
%bothopt(_) ->
% false.
runopt(notempty) ->
true;
runopt(notbol) ->
true;
runopt(noteol) ->
true;
runopt({offset,_}) ->
true;
runopt({capture,_,_}) ->
true;
runopt({capture,_}) ->
true;
runopt(global) ->
true;
runopt(_) ->
false.
to_binary(Bin, _IsUnicode) when is_binary(Bin) ->
Bin;
to_binary(Data, true) ->
unicode:characters_to_binary(Data,unicode);
to_binary(Data, false) ->
iolist_to_binary(Data).
