diff options
Diffstat (limited to 'lib/stdlib/src/string.erl')
| -rw-r--r-- | lib/stdlib/src/string.erl | 1266 |
1 files changed, 1245 insertions, 21 deletions
diff --git a/lib/stdlib/src/string.erl b/lib/stdlib/src/string.erl index c659db78bd..4fdfe99b66 100644 --- a/lib/stdlib/src/string.erl +++ b/lib/stdlib/src/string.erl @@ -17,22 +17,72 @@ %% %% %CopyrightEnd% %% +%% A string library that works on grapheme clusters, with the exception +%% of codepoints of class 'prepend' and non modern (or decomposed) Hangul. +%% If these codepoints appear, functions like 'find/2' may return a string +%% which starts inside a grapheme cluster. +%% These exceptions are made because the codepoints classes are +%% seldom used and require that we are able look at previous codepoints in +%% the stream and is thus hard to implement effectively. +%% +%% GC (grapheme cluster) implies that the length of string 'ß↑e̊' is 3 though +%% it is represented by the codepoints [223,8593,101,778] or the +%% utf8 binary <<195,159,226,134,145,101,204,138>> +%% +%% And that searching for strings or graphemes finds the correct positions: +%% +%% find("eeeee̊eee", "e̊") -> "e̊ee".: +%% find("1£4e̊abcdef", "e") -> "ef" +%% +%% Most functions expect all input to be normalized to one form, +%% see unicode:characters_to_nfc and unicode:characters_to_nfd functions. +%% When appending strings no checking is done to verify that the +%% result is valid unicode strings. +%% +%% The functions may crash for invalid utf-8 input. +%% +%% Return value should be kept consistent when return type is +%% unicode:chardata() i.e. binary input => binary output, +%% list input => list output mixed input => mixed output +%% -module(string). --export([len/1,equal/2,concat/2,chr/2,rchr/2,str/2,rstr/2, - span/2,cspan/2,substr/2,substr/3,tokens/2,chars/2,chars/3]). +-export([is_empty/1, length/1, to_graphemes/1, + reverse/1, + equal/2, equal/3, equal/4, + slice/2, slice/3, + pad/2, pad/3, pad/4, trim/1, trim/2, trim/3, chomp/1, + take/2, take/3, take/4, + lexemes/2, nth_lexeme/3, + uppercase/1, lowercase/1, titlecase/1,casefold/1, + prefix/2, + split/2,split/3,replace/3,replace/4, + find/2,find/3, + next_codepoint/1, next_grapheme/1 + ]). + +%% Old (will be deprecated) lists/string API kept for backwards compability +-export([len/1, concat/2, % equal/2, (extended in the new api) + chr/2,rchr/2,str/2,rstr/2, + span/2,cspan/2,substr/2,substr/3, tokens/2, + chars/2,chars/3]). -export([copies/2,words/1,words/2,strip/1,strip/2,strip/3, sub_word/2,sub_word/3,left/2,left/3,right/2,right/3, sub_string/2,sub_string/3,centre/2,centre/3, join/2]). -export([to_upper/1, to_lower/1]). +%% +-import(lists,[member/2]). --import(lists,[reverse/1,member/2]). +-compile({no_auto_import,[length/1]}). -%%--------------------------------------------------------------------------- +-export_type([grapheme_cluster/0]). -%%% BIFs +-type grapheme_cluster() :: char() | [char()]. +-type direction() :: 'leading' | 'trailing'. +%%% BIFs -export([to_float/1, to_integer/1]). +-dialyzer({no_improper_lists, stack/2}). -spec to_float(String) -> {Float, Rest} | {error, Reason} when String :: string(), @@ -54,6 +104,1180 @@ to_integer(_) -> %%% End of BIFs +%% Check if string is the empty string +-spec is_empty(String::unicode:chardata()) -> boolean(). +is_empty([]) -> true; +is_empty(<<>>) -> true; +is_empty([L|R]) -> is_empty(L) andalso is_empty(R); +is_empty(_) -> false. + +%% Count the number of grapheme clusters in chardata +-spec length(String::unicode:chardata()) -> non_neg_integer(). +length(CD) -> + length_1(unicode_util:gc(CD), 0). + +%% Convert a string to a list of grapheme clusters +-spec to_graphemes(String::unicode:chardata()) -> [grapheme_cluster()]. +to_graphemes(CD0) -> + case unicode_util:gc(CD0) of + [GC|CD] -> [GC|to_graphemes(CD)]; + [] -> [] + end. + +%% Compare two strings return boolean, assumes that the input are +%% normalized to same form, see unicode:characters_to_nfX_xxx(..) +-spec equal(A, B) -> boolean() when + A::unicode:chardata(), + B::unicode:chardata(). +equal(A,B) when is_binary(A), is_binary(B) -> + A =:= B; +equal(A,B) -> + equal_1(A,B). + +%% Compare two strings return boolean, assumes that the input are +%% normalized to same form, see unicode:characters_to_nfX_xxx(..) +%% does casefold on the fly +-spec equal(A, B, IgnoreCase) -> boolean() when + A::unicode:chardata(), + B::unicode:chardata(), + IgnoreCase :: boolean(). +equal(A, B, false) -> + equal(A,B); +equal(A, B, true) -> + equal_nocase(A,B). + +%% Compare two strings return boolean +%% if specified does casefold and normalization on the fly +-spec equal(A, B, IgnoreCase, Norm) -> boolean() when + A :: unicode:chardata(), + B :: unicode:chardata(), + IgnoreCase :: boolean(), + Norm :: 'none' | 'nfc' | 'nfd' | 'nfkc' | 'nfkd'. +equal(A, B, Case, none) -> + equal(A,B,Case); +equal(A, B, false, Norm) -> + equal_norm(A, B, Norm); +equal(A, B, true, Norm) -> + equal_norm_nocase(A, B, Norm). + +%% Reverse grapheme clusters +-spec reverse(String::unicode:chardata()) -> [grapheme_cluster()]. +reverse(CD) -> + reverse_1(CD, []). + +%% Slice a string and return rest of string +%% Note: counts grapheme_clusters +-spec slice(String, Start) -> Slice when + String::unicode:chardata(), + Start :: non_neg_integer(), + Slice :: unicode:chardata(). +slice(CD, N) when is_integer(N), N >= 0 -> + slice_l(CD, N, is_binary(CD)). + +-spec slice(String, Start, Length) -> Slice when + String::unicode:chardata(), + Start :: non_neg_integer(), + Length :: 'infinity' | non_neg_integer(), + Slice :: unicode:chardata(). +slice(CD, N, Length) + when is_integer(N), N >= 0, is_integer(Length), Length > 0 -> + slice_trail(slice_l(CD, N, is_binary(CD)), Length); +slice(CD, N, infinity) -> + slice_l(CD, N, is_binary(CD)); +slice(CD, _, 0) -> + case is_binary(CD) of + true -> <<>>; + false -> [] + end. + +%% Pad a string to desired length +-spec pad(String, Length) -> unicode:charlist() when + String ::unicode:chardata(), + Length :: integer(). +pad(CD, Length) -> + pad(CD, Length, trailing, $\s). + +-spec pad(String, Length, Dir) -> unicode:charlist() when + String ::unicode:chardata(), + Length :: integer(), + Dir :: direction() | 'both'. +pad(CD, Length, Dir) -> + pad(CD, Length, Dir, $\s). + +-spec pad(String, Length, Dir, Char) -> unicode:charlist() when + String ::unicode:chardata(), + Length :: integer(), + Dir :: direction() | 'both', + Char :: grapheme_cluster(). +pad(CD, Length, leading, Char) when is_integer(Length) -> + Len = length(CD), + [lists:duplicate(max(0, Length-Len), Char), CD]; +pad(CD, Length, trailing, Char) when is_integer(Length) -> + Len = length(CD), + [CD|lists:duplicate(max(0, Length-Len), Char)]; +pad(CD, Length, both, Char) when is_integer(Length) -> + Len = length(CD), + Size = max(0, Length-Len), + Pre = lists:duplicate(Size div 2, Char), + Post = case Size rem 2 of + 1 -> [Char]; + _ -> [] + end, + [Pre, CD, Pre|Post]. + +%% Strip characters from whitespace or Separator in Direction +-spec trim(String) -> unicode:chardata() when + String :: unicode:chardata(). +trim(Str) -> + trim(Str, both, unicode_util:whitespace()). + +-spec trim(String, Dir) -> unicode:chardata() when + String :: unicode:chardata(), + Dir :: direction() | 'both'. +trim(Str, Dir) -> + trim(Str, Dir, unicode_util:whitespace()). + +-spec trim(String, Dir, Characters) -> unicode:chardata() when + String :: unicode:chardata(), + Dir :: direction() | 'both', + Characters :: [grapheme_cluster()]. +trim(Str, _, []) -> Str; +trim(Str, leading, Sep) when is_list(Sep) -> + trim_l(Str, search_pattern(Sep)); +trim(Str, trailing, Sep) when is_list(Sep) -> + trim_t(Str, 0, search_pattern(Sep)); +trim(Str, both, Sep0) when is_list(Sep0) -> + Sep = search_pattern(Sep0), + trim_t(trim_l(Str,Sep), 0, Sep). + +%% Delete trailing newlines or \r\n +-spec chomp(String::unicode:chardata()) -> unicode:chardata(). +chomp(Str) -> + trim_t(Str,0, {[[$\r,$\n],$\n], [$\r,$\n], [<<$\r>>,<<$\n>>]}). + +%% Split String into two parts where the leading part consists of Characters +-spec take(String, Characters) -> {Leading, Trailing} when + String::unicode:chardata(), + Characters::[grapheme_cluster()], + Leading::unicode:chardata(), + Trailing::unicode:chardata(). +take(Str, Sep) -> + take(Str, Sep, false, leading). +-spec take(String, Characters, Complement) -> {Leading, Trailing} when + String::unicode:chardata(), + Characters::[grapheme_cluster()], + Complement::boolean(), + Leading::unicode:chardata(), + Trailing::unicode:chardata(). +take(Str, Sep, Complement) -> + take(Str, Sep, Complement, leading). +-spec take(String, Characters, Complement, Dir) -> {Leading, Trailing} when + String::unicode:chardata(), + Characters::[grapheme_cluster()], + Complement::boolean(), + Dir::direction(), + Leading::unicode:chardata(), + Trailing::unicode:chardata(). +take(Str, [], Complement, Dir) -> + Empty = case is_binary(Str) of true -> <<>>; false -> [] end, + case {Complement,Dir} of + {false, leading} -> {Empty, Str}; + {false, trailing} -> {Str, Empty}; + {true, leading} -> {Str, Empty}; + {true, trailing} -> {Empty, Str} + end; +take(Str, Sep0, false, leading) -> + Sep = search_pattern(Sep0), + take_l(Str, Sep, []); +take(Str, Sep0, true, leading) -> + Sep = search_pattern(Sep0), + take_lc(Str, Sep, []); +take(Str, Sep0, false, trailing) -> + Sep = search_pattern(Sep0), + take_t(Str, 0, Sep); +take(Str, Sep0, true, trailing) -> + Sep = search_pattern(Sep0), + take_tc(Str, 0, Sep). + +%% Uppercase all chars in Str +-spec uppercase(String::unicode:chardata()) -> unicode:chardata(). +uppercase(CD) when is_list(CD) -> + uppercase_list(CD); +uppercase(CD) when is_binary(CD) -> + uppercase_bin(CD,<<>>). + +%% Lowercase all chars in Str +-spec lowercase(String::unicode:chardata()) -> unicode:chardata(). +lowercase(CD) when is_list(CD) -> + lowercase_list(CD); +lowercase(CD) when is_binary(CD) -> + lowercase_bin(CD,<<>>). + +%% Make a titlecase of the first char in Str +-spec titlecase(String::unicode:chardata()) -> unicode:chardata(). +titlecase(CD) when is_list(CD) -> + case unicode_util:titlecase(CD) of + [GC|Tail] -> append(GC,Tail); + Empty -> Empty + end; +titlecase(CD) when is_binary(CD) -> + case unicode_util:titlecase(CD) of + [CP|Chars] when is_integer(CP) -> <<CP/utf8,Chars/binary>>; + [CPs|Chars] -> + << << <<CP/utf8>> || CP <- CPs>>/binary, Chars/binary>>; + [] -> <<>> + end. + +%% Make a comparable string of the Str should be used for equality tests only +-spec casefold(String::unicode:chardata()) -> unicode:chardata(). +casefold(CD) when is_list(CD) -> + casefold_list(CD); +casefold(CD) when is_binary(CD) -> + casefold_bin(CD,<<>>). + +%% Return the remaining string with prefix removed or else nomatch +-spec prefix(String::unicode:chardata(), Prefix::unicode:chardata()) -> + 'nomatch' | unicode:chardata(). +prefix(Str, []) -> Str; +prefix(Str, Prefix0) -> + Prefix = unicode:characters_to_list(Prefix0), + case prefix_1(Str, Prefix) of + [] when is_binary(Str) -> <<>>; + Res -> Res + end. + +%% split String with the first occurrence of SearchPattern, return list of splits +-spec split(String, SearchPattern) -> [unicode:chardata()] when + String :: unicode:chardata(), + SearchPattern :: unicode:chardata(). +split(String, SearchPattern) -> + split(String, SearchPattern, leading). + +%% split String with SearchPattern, return list of splits +-spec split(String, SearchPattern, Where) -> [unicode:chardata()] when + String :: unicode:chardata(), + SearchPattern :: unicode:chardata(), + Where :: direction() | 'all'. +split(String, SearchPattern, Where) -> + case is_empty(SearchPattern) of + true -> [String]; + false -> + SearchPatternCPs = unicode:characters_to_list(SearchPattern), + case split_1(String, SearchPatternCPs, 0, Where, [], []) of + {_Curr, []} -> [String]; + {_Curr, Acc} when Where =:= trailing -> Acc; + {Curr, Acc} when Where =:= all -> lists:reverse([Curr|Acc]); + Acc when is_list(Acc) -> Acc + end + end. + +%% Replace the first SearchPattern in String with Replacement +-spec replace(String, SearchPattern, Replacement) -> + [unicode:chardata()] when + String :: unicode:chardata(), + SearchPattern :: unicode:chardata(), + Replacement :: unicode:chardata(). +replace(String, SearchPattern, Replacement) -> + lists:join(Replacement, split(String, SearchPattern)). + +%% Replace Where SearchPattern in String with Replacement +-spec replace(String, SearchPattern, Replacement, Where) -> + [unicode:chardata()] when + String :: unicode:chardata(), + SearchPattern :: unicode:chardata(), + Replacement :: unicode:chardata(), + Where :: direction() | 'all'. +replace(String, SearchPattern, Replacement, Where) -> + lists:join(Replacement, split(String, SearchPattern, Where)). + +%% Split Str into a list of chardata separated by one of the grapheme +%% clusters in Seps +-spec lexemes(String::unicode:chardata(), + SeparatorList::[grapheme_cluster()]) -> + [unicode:chardata()]. +lexemes([], _) -> []; +lexemes(Str, Seps0) when is_list(Seps0) -> + Seps = search_pattern(Seps0), + lexemes_m(Str, Seps, []). + +-spec nth_lexeme(String, N, SeparatorList) -> unicode:chardata() when + String::unicode:chardata(), + N::non_neg_integer(), + SeparatorList::[grapheme_cluster()]. + +nth_lexeme(Str, 1, []) -> Str; +nth_lexeme(Str, N, Seps0) when is_list(Seps0), is_integer(N), N > 0 -> + Seps = search_pattern(Seps0), + nth_lexeme_m(Str, Seps, N). + +%% find first SearchPattern in String return rest of string +-spec find(String, SearchPattern) -> unicode:chardata() | 'nomatch' when + String::unicode:chardata(), + SearchPattern::unicode:chardata(). +find(String, SearchPattern) -> + find(String, SearchPattern, leading). + +%% find SearchPattern in String (search in Dir direction) return rest of string +-spec find(String, SearchPattern, Dir) -> unicode:chardata() | 'nomatch' when + String::unicode:chardata(), + SearchPattern::unicode:chardata(), + Dir::direction(). +find(String, "", _) -> String; +find(String, <<>>, _) -> String; +find(String, SearchPattern, leading) -> + find_l(String, unicode:characters_to_list(SearchPattern)); +find(String, SearchPattern, trailing) -> + find_r(String, unicode:characters_to_list(SearchPattern), nomatch). + +%% Fetch first codepoint and return rest in tail +-spec next_grapheme(String::unicode:chardata()) -> + maybe_improper_list(grapheme_cluster(),unicode:chardata()). +next_grapheme(CD) -> unicode_util:gc(CD). + +%% Fetch first grapheme cluster and return rest in tail +-spec next_codepoint(String::unicode:chardata()) -> + maybe_improper_list(char(),unicode:chardata()). +next_codepoint(CD) -> unicode_util:cp(CD). + +%% Internals + +length_1([_|Rest], N) -> + length_1(unicode_util:gc(Rest), N+1); +length_1([], N) -> + N. + +equal_1([A|AR], [B|BR]) when is_integer(A), is_integer(B) -> + A =:= B andalso equal_1(AR, BR); +equal_1([], BR) -> is_empty(BR); +equal_1(A0,B0) -> + case {unicode_util:cp(A0), unicode_util:cp(B0)} of + {[CP|A],[CP|B]} -> equal_1(A,B); + {[], []} -> true; + _ -> false + end. + +equal_nocase(A, A) -> true; +equal_nocase(A0, B0) -> + case {unicode_util:cp(unicode_util:casefold(A0)), + unicode_util:cp(unicode_util:casefold(B0))} of + {[CP|A],[CP|B]} -> equal_nocase(A,B); + {[], []} -> true; + _ -> false + end. + +equal_norm(A, A, _Norm) -> true; +equal_norm(A0, B0, Norm) -> + case {unicode_util:cp(unicode_util:Norm(A0)), + unicode_util:cp(unicode_util:Norm(B0))} of + {[CP|A],[CP|B]} -> equal_norm(A,B, Norm); + {[], []} -> true; + _ -> false + end. + +equal_norm_nocase(A, A, _Norm) -> true; +equal_norm_nocase(A0, B0, Norm) -> + case {unicode_util:cp(unicode_util:casefold(unicode_util:Norm(A0))), + unicode_util:cp(unicode_util:casefold(unicode_util:Norm(B0)))} of + {[CP|A],[CP|B]} -> equal_norm_nocase(A,B, Norm); + {[], []} -> true; + _ -> false + end. + +reverse_1(CD, Acc) -> + case unicode_util:gc(CD) of + [GC|Rest] -> reverse_1(Rest, [GC|Acc]); + [] -> Acc + end. + +slice_l(CD, N, Binary) when N > 0 -> + case unicode_util:gc(CD) of + [_|Cont] -> slice_l(Cont, N-1, Binary); + [] when Binary -> <<>>; + [] -> [] + end; +slice_l(Cont, 0, Binary) -> + case is_empty(Cont) of + true when Binary -> <<>>; + _ -> Cont + end. + +slice_trail(CD, N) when is_list(CD) -> + slice_list(CD, N); +slice_trail(CD, N) when is_binary(CD) -> + slice_bin(CD, N, CD). + +slice_list(CD, N) when N > 0 -> + case unicode_util:gc(CD) of + [GC|Cont] -> append(GC, slice_list(Cont, N-1)); + [] -> [] + end; +slice_list(_, 0) -> + []. + +slice_bin(CD, N, Orig) when N > 0 -> + case unicode_util:gc(CD) of + [_|Cont] -> slice_bin(Cont, N-1, Orig); + [] -> Orig + end; +slice_bin([], 0, Orig) -> + Orig; +slice_bin(CD, 0, Orig) -> + Sz = byte_size(Orig) - byte_size(CD), + <<Keep:Sz/binary, _/binary>> = Orig, + Keep. + +uppercase_list(CPs0) -> + case unicode_util:uppercase(CPs0) of + [Char|CPs] -> append(Char,uppercase_list(CPs)); + [] -> [] + end. + +uppercase_bin(CPs0, Acc) -> + case unicode_util:uppercase(CPs0) of + [Char|CPs] when is_integer(Char) -> + uppercase_bin(CPs, <<Acc/binary, Char/utf8>>); + [Chars|CPs] -> + uppercase_bin(CPs, <<Acc/binary, + << <<CP/utf8>> || CP <- Chars>>/binary >>); + [] -> Acc + end. + +lowercase_list(CPs0) -> + case unicode_util:lowercase(CPs0) of + [Char|CPs] -> append(Char,lowercase_list(CPs)); + [] -> [] + end. + +lowercase_bin(CPs0, Acc) -> + case unicode_util:lowercase(CPs0) of + [Char|CPs] when is_integer(Char) -> + lowercase_bin(CPs, <<Acc/binary, Char/utf8>>); + [Chars|CPs] -> + lowercase_bin(CPs, <<Acc/binary, + << <<CP/utf8>> || CP <- Chars>>/binary >>); + [] -> Acc + end. + +casefold_list(CPs0) -> + case unicode_util:casefold(CPs0) of + [Char|CPs] -> append(Char, casefold_list(CPs)); + [] -> [] + end. + +casefold_bin(CPs0, Acc) -> + case unicode_util:casefold(CPs0) of + [Char|CPs] when is_integer(Char) -> + casefold_bin(CPs, <<Acc/binary, Char/utf8>>); + [Chars|CPs] -> + casefold_bin(CPs, <<Acc/binary, + << <<CP/utf8>> || CP <- Chars>>/binary >>); + [] -> Acc + end. + + +trim_l([Bin|Cont0], Sep) when is_binary(Bin) -> + case bin_search_inv(Bin, Cont0, Sep) of + {nomatch, Cont} -> trim_l(Cont, Sep); + Keep -> Keep + end; +trim_l(Str, {GCs, _, _}=Sep) when is_list(Str) -> + case unicode_util:gc(Str) of + [C|Cs] -> + case lists:member(C, GCs) of + true -> trim_l(Cs, Sep); + false -> Str + end; + [] -> [] + end; +trim_l(Bin, Sep) when is_binary(Bin) -> + case bin_search_inv(Bin, [], Sep) of + {nomatch,_} -> <<>>; + [Keep] -> Keep + end. + +trim_t([Bin|Cont0], N, Sep) when is_binary(Bin) -> + <<_:N/binary, Rest/binary>> = Bin, + case bin_search(Rest, Cont0, Sep) of + {nomatch,_} -> + stack(Bin, trim_t(Cont0, 0, Sep)); + [SepStart|Cont1] -> + case bin_search_inv(SepStart, Cont1, Sep) of + {nomatch, Cont} -> + Tail = trim_t(Cont, 0, Sep), + case is_empty(Tail) of + true -> + KeepSz = byte_size(Bin) - byte_size(SepStart), + <<Keep:KeepSz/binary, _/binary>> = Bin, + Keep; + false -> + Used = cp_prefix(Cont0, Cont), + stack(Bin, stack(Used, Tail)) + end; + [NonSep|Cont] when is_binary(NonSep) -> + KeepSz = byte_size(Bin) - byte_size(NonSep), + trim_t([Bin|Cont], KeepSz, Sep) + end + end; +trim_t(Str, 0, {GCs,CPs,_}=Sep) when is_list(Str) -> + case unicode_util:cp(Str) of + [CP|Cs] -> + case lists:member(CP, CPs) of + true -> + [GC|Cs1] = unicode_util:gc(Str), + case lists:member(GC, GCs) of + true -> + Tail = trim_t(Cs1, 0, Sep), + case is_empty(Tail) of + true -> []; + false -> append(GC,Tail) + end; + false -> + append(GC,trim_t(Cs1, 0, Sep)) + end; + false -> + append(CP,trim_t(Cs, 0, Sep)) + end; + [] -> [] + end; +trim_t(Bin, N, Sep) when is_binary(Bin) -> + <<_:N/binary, Rest/binary>> = Bin, + case bin_search(Rest, Sep) of + {nomatch,_} -> Bin; + [SepStart] -> + case bin_search_inv(SepStart, [], Sep) of + {nomatch,_} -> + KeepSz = byte_size(Bin) - byte_size(SepStart), + <<Keep:KeepSz/binary, _/binary>> = Bin, + Keep; + [NonSep] -> + KeepSz = byte_size(Bin) - byte_size(NonSep), + trim_t(Bin, KeepSz, Sep) + end + end. + +take_l([Bin|Cont0], Sep, Acc) when is_binary(Bin) -> + case bin_search_inv(Bin, Cont0, Sep) of + {nomatch, Cont} -> + Used = cp_prefix(Cont0, Cont), + take_l(Cont, Sep, [unicode:characters_to_binary([Bin|Used])|Acc]); + [Bin1|_]=After when is_binary(Bin1) -> + First = byte_size(Bin) - byte_size(Bin1), + <<Keep:First/binary, _/binary>> = Bin, + {btoken(Keep,Acc), After} + end; +take_l(Str, {GCs, _, _}=Sep, Acc) when is_list(Str) -> + case unicode_util:gc(Str) of + [C|Cs] -> + case lists:member(C, GCs) of + true -> take_l(Cs, Sep, append(rev(C),Acc)); + false -> {rev(Acc), Str} + end; + [] -> {rev(Acc), []} + end; +take_l(Bin, Sep, Acc) when is_binary(Bin) -> + case bin_search_inv(Bin, [], Sep) of + {nomatch,_} -> + {btoken(Bin, Acc), <<>>}; + [After] -> + First = byte_size(Bin) - byte_size(After), + <<Keep:First/binary, _/binary>> = Bin, + {btoken(Keep, Acc), After} + end. + +take_lc([Bin|Cont0], Sep, Acc) when is_binary(Bin) -> + case bin_search(Bin, Cont0, Sep) of + {nomatch, Cont} -> + Used = cp_prefix(Cont0, Cont), + take_lc(Cont, Sep, [unicode:characters_to_binary([Bin|Used])|Acc]); + [Bin1|_]=After when is_binary(Bin1) -> + First = byte_size(Bin) - byte_size(Bin1), + <<Keep:First/binary, _/binary>> = Bin, + {btoken(Keep,Acc), After} + end; +take_lc(Str, {GCs, _, _}=Sep, Acc) when is_list(Str) -> + case unicode_util:gc(Str) of + [C|Cs] -> + case lists:member(C, GCs) of + false -> take_lc(Cs, Sep, append(rev(C),Acc)); + true -> {rev(Acc), Str} + end; + [] -> {rev(Acc), []} + end; +take_lc(Bin, Sep, Acc) when is_binary(Bin) -> + case bin_search(Bin, [], Sep) of + {nomatch,_} -> + {btoken(Bin, Acc), <<>>}; + [After] -> + First = byte_size(Bin) - byte_size(After), + <<Keep:First/binary, _/binary>> = Bin, + {btoken(Keep, Acc), After} + end. + +take_t([Bin|Cont0], N, Sep) when is_binary(Bin) -> + <<_:N/binary, Rest/binary>> = Bin, + case bin_search(Rest, Cont0, Sep) of + {nomatch,Cont} -> + Used = cp_prefix(Cont0, Cont), + {Head, Tail} = take_t(Cont, 0, Sep), + {stack(unicode:characters_to_binary([Bin|Used]), Head), Tail}; + [SepStart|Cont1] -> + case bin_search_inv(SepStart, Cont1, Sep) of + {nomatch, Cont} -> + {Head, Tail} = take_t(Cont, 0, Sep), + Used = cp_prefix(Cont0, Cont), + case equal(Tail, Cont) of + true -> + KeepSz = byte_size(Bin) - byte_size(SepStart), + <<Keep:KeepSz/binary, End/binary>> = Bin, + {stack(Keep,Head), stack(stack(End,Used),Tail)}; + false -> + {stack(unicode:characters_to_binary([Bin|Used]),Head), Tail} + end; + [NonSep|Cont] when is_binary(NonSep) -> + KeepSz = byte_size(Bin) - byte_size(NonSep), + take_t([Bin|Cont], KeepSz, Sep) + end + end; +take_t(Str, 0, {GCs,CPs,_}=Sep) when is_list(Str) -> + case unicode_util:cp(Str) of + [CP|Cs] -> + case lists:member(CP, CPs) of + true -> + [GC|Cs1] = unicode_util:gc(Str), + case lists:member(GC, GCs) of + true -> + {Head, Tail} = take_t(Cs1, 0, Sep), + case equal(Tail, Cs1) of + true -> {Head, append(GC,Tail)}; + false -> {append(GC,Head), Tail} + end; + false -> + {Head, Tail} = take_t(Cs, 0, Sep), + {append(CP,Head), Tail} + end; + false -> + {Head, Tail} = take_t(Cs, 0, Sep), + {append(CP,Head), Tail} + end; + [] -> {[],[]} + end; +take_t(Bin, N, Sep) when is_binary(Bin) -> + <<_:N/binary, Rest/binary>> = Bin, + case bin_search(Rest, Sep) of + {nomatch,_} -> {Bin, <<>>}; + [SepStart] -> + case bin_search_inv(SepStart, [], Sep) of + {nomatch,_} -> + KeepSz = byte_size(Bin) - byte_size(SepStart), + <<Before:KeepSz/binary, End/binary>> = Bin, + {Before, End}; + [NonSep] -> + KeepSz = byte_size(Bin) - byte_size(NonSep), + take_t(Bin, KeepSz, Sep) + end + end. + +take_tc([Bin|Cont0], N, Sep) when is_binary(Bin) -> + <<_:N/binary, Rest/binary>> = Bin, + case bin_search_inv(Rest, Cont0, Sep) of + {nomatch,Cont} -> + Used = cp_prefix(Cont0, Cont), + {Head, Tail} = take_tc(Cont, 0, Sep), + {stack(unicode:characters_to_binary([Bin|Used]), Head), Tail}; + [SepStart|Cont1] -> + case bin_search(SepStart, Cont1, Sep) of + {nomatch, Cont} -> + {Head, Tail} = take_tc(Cont, 0, Sep), + Used = cp_prefix(Cont0, Cont), + case equal(Tail, Cont) of + true -> + KeepSz = byte_size(Bin) - byte_size(SepStart), + <<Keep:KeepSz/binary, End/binary>> = Bin, + {stack(Keep,Head), stack(stack(End,Used),Tail)}; + false -> + {stack(unicode:characters_to_binary([Bin|Used]),Head), Tail} + end; + [NonSep|Cont] when is_binary(NonSep) -> + KeepSz = byte_size(Bin) - byte_size(NonSep), + take_tc([Bin|Cont], KeepSz, Sep) + end + end; +take_tc(Str, 0, {GCs,CPs,_}=Sep) when is_list(Str) -> + case unicode_util:cp(Str) of + [CP|Cs] -> + case lists:member(CP, CPs) of + true -> + [GC|Cs1] = unicode_util:gc(Str), + case lists:member(GC, GCs) of + false -> + {Head, Tail} = take_tc(Cs1, 0, Sep), + case equal(Tail, Cs1) of + true -> {Head, append(GC,Tail)}; + false -> {append(GC,Head), Tail} + end; + true -> + {Head, Tail} = take_tc(Cs1, 0, Sep), + {append(GC,Head), Tail} + end; + false -> + {Head, Tail} = take_tc(Cs, 0, Sep), + case equal(Tail, Cs) of + true -> {Head, append(CP,Tail)}; + false -> {append(CP,Head), Tail} + end + end; + [] -> {[],[]} + end; +take_tc(Bin, N, Sep) when is_binary(Bin) -> + <<_:N/binary, Rest/binary>> = Bin, + case bin_search_inv(Rest, [], Sep) of + {nomatch,_} -> {Bin, <<>>}; + [SepStart] -> + case bin_search(SepStart, [], Sep) of + {nomatch,_} -> + KeepSz = byte_size(Bin) - byte_size(SepStart), + <<Before:KeepSz/binary, End/binary>> = Bin, + {Before, End}; + [NonSep] -> + KeepSz = byte_size(Bin) - byte_size(NonSep), + take_tc(Bin, KeepSz, Sep) + end + end. + +prefix_1(Cs, []) -> Cs; +prefix_1(Cs, [_]=Pre) -> + prefix_2(unicode_util:gc(Cs), Pre); +prefix_1(Cs, Pre) -> + prefix_2(unicode_util:cp(Cs), Pre). + +prefix_2([C|Cs], [C|Pre]) -> + prefix_1(Cs, Pre); +prefix_2(_, _) -> + nomatch. + +split_1([Bin|Cont0], Needle, Start, Where, Curr0, Acc) + when is_binary(Bin) -> + case bin_search_str(Bin, Start, Cont0, Needle) of + {nomatch,Sz,Cont} -> + <<Keep:Sz/binary, _/binary>> = Bin, + split_1(Cont, Needle, 0, Where, [Keep|Curr0], Acc); + {Before, [Cs0|Cont], After} -> + Curr = add_non_empty(Before,Curr0), + case Where of + leading -> + [rev(Curr),After]; + trailing -> + <<_/utf8, Cs/binary>> = Cs0, + Next = byte_size(Bin) - byte_size(Cs), + split_1([Bin|Cont], Needle, Next, Where, + Curr0, [rev(Curr),After]); + all -> + split_1(After, Needle, 0, Where, [], [rev(Curr)|Acc]) + end + end; +split_1(Cs0, [C|_]=Needle, _, Where, Curr, Acc) when is_list(Cs0) -> + case unicode_util:cp(Cs0) of + [C|Cs] -> + case prefix_1(Cs0, Needle) of + nomatch -> split_1(Cs, Needle, 0, Where, append(C,Curr), Acc); + Rest when Where =:= leading -> + [rev(Curr), Rest]; + Rest when Where =:= trailing -> + split_1(Cs, Needle, 0, Where, [C|Curr], [rev(Curr), Rest]); + Rest when Where =:= all -> + split_1(Rest, Needle, 0, Where, [], [rev(Curr)|Acc]) + end; + [Other|Cs] -> + split_1(Cs, Needle, 0, Where, append(Other,Curr), Acc); + [] -> + {rev(Curr), Acc} + end; +split_1(Bin, [_C|_]=Needle, Start, Where, Curr0, Acc) -> + case bin_search_str(Bin, Start, [], Needle) of + {nomatch,_,_} -> + <<_:Start/binary, Keep/binary>> = Bin, + {rev([Keep|Curr0]), Acc}; + {Before, [Cs0], After} -> + case Where of + leading -> + [rev([Before|Curr0]),After]; + trailing -> + <<_/utf8, Cs/binary>> = Cs0, + Next = byte_size(Bin) - byte_size(Cs), + split_1(Bin, Needle, Next, Where, Curr0, + [btoken(Before,Curr0),After]); + all -> + Next = byte_size(Bin) - byte_size(After), + <<_:Start/binary, Keep/binary>> = Before, + Curr = [Keep|Curr0], + split_1(Bin, Needle, Next, Where, [], [rev(Curr)|Acc]) + end + end. + +lexemes_m([Bin|Cont0], Seps, Ts) when is_binary(Bin) -> + case bin_search_inv(Bin, Cont0, Seps) of + {nomatch,Cont} -> + lexemes_m(Cont, Seps, Ts); + Cs -> + {Lexeme,Rest} = lexeme_pick(Cs, Seps, []), + lexemes_m(Rest, Seps, [Lexeme|Ts]) + end; +lexemes_m(Cs0, {GCs, _, _}=Seps, Ts) when is_list(Cs0) -> + case unicode_util:gc(Cs0) of + [C|Cs] -> + case lists:member(C, GCs) of + true -> + lexemes_m(Cs, Seps, Ts); + false -> + {Lexeme,Rest} = lexeme_pick(Cs0, Seps, []), + lexemes_m(Rest, Seps, [Lexeme|Ts]) + end; + [] -> + lists:reverse(Ts) + end; +lexemes_m(Bin, Seps, Ts) when is_binary(Bin) -> + case bin_search_inv(Bin, [], Seps) of + {nomatch,_} -> + lists:reverse(Ts); + [Cs] -> + {Lexeme,Rest} = lexeme_pick(Cs, Seps, []), + lexemes_m(Rest, Seps, add_non_empty(Lexeme,Ts)) + end. + +lexeme_pick([CP|Cs1]=Cs0, {GCs,CPs,_}=Seps, Tkn) when is_integer(CP) -> + case lists:member(CP, CPs) of + true -> + [GC|Cs2] = unicode_util:gc(Cs0), + case lists:member(GC, GCs) of + true -> {rev(Tkn), Cs2}; + false -> lexeme_pick(Cs2, Seps, append(rev(GC),Tkn)) + end; + false -> lexeme_pick(Cs1, Seps, [CP|Tkn]) + end; +lexeme_pick([Bin|Cont0], Seps, Tkn) when is_binary(Bin) -> + case bin_search(Bin, Cont0, Seps) of + {nomatch,_} -> + lexeme_pick(Cont0, Seps, [Bin|Tkn]); + [Left|_Cont] = Cs -> + Bytes = byte_size(Bin) - byte_size(Left), + <<Lexeme:Bytes/binary, _/binary>> = Bin, + {btoken(Lexeme, Tkn), Cs} + end; +lexeme_pick(Cs0, {GCs, CPs, _} = Seps, Tkn) when is_list(Cs0) -> + case unicode_util:cp(Cs0) of + [CP|Cs] -> + case lists:member(CP, CPs) of + true -> + [GC|Cs2] = unicode_util:gc(Cs0), + case lists:member(GC, GCs) of + true -> {rev(Tkn), Cs0}; + false -> lexeme_pick(Cs2, Seps, append(rev(GC),Tkn)) + end; + false -> + lexeme_pick(Cs, Seps, append(CP,Tkn)) + end; + [] -> + {rev(Tkn), []} + end; +lexeme_pick(Bin, Seps, Tkn) when is_binary(Bin) -> + case bin_search(Bin, Seps) of + {nomatch,_} -> + {btoken(Bin,Tkn), []}; + [Left] -> + Bytes = byte_size(Bin) - byte_size(Left), + <<Lexeme:Bytes/binary, _/binary>> = Bin, + {btoken(Lexeme, Tkn), Left} + end. + +nth_lexeme_m([Bin|Cont0], Seps, N) when is_binary(Bin) -> + case bin_search_inv(Bin, Cont0, Seps) of + {nomatch,Cont} -> + nth_lexeme_m(Cont, Seps, N); + Cs when N > 1 -> + Rest = lexeme_skip(Cs, Seps), + nth_lexeme_m(Rest, Seps, N-1); + Cs -> + {Lexeme,_} = lexeme_pick(Cs, Seps, []), + Lexeme + end; +nth_lexeme_m(Cs0, {GCs, _, _}=Seps, N) when is_list(Cs0) -> + case unicode_util:gc(Cs0) of + [C|Cs] -> + case lists:member(C, GCs) of + true -> + nth_lexeme_m(Cs, Seps, N); + false when N > 1 -> + Cs1 = lexeme_skip(Cs, Seps), + nth_lexeme_m(Cs1, Seps, N-1); + false -> + {Lexeme,_} = lexeme_pick(Cs0, Seps, []), + Lexeme + end; + [] -> + [] + end; +nth_lexeme_m(Bin, Seps, N) when is_binary(Bin) -> + case bin_search_inv(Bin, [], Seps) of + [Cs] when N > 1 -> + Cs1 = lexeme_skip(Cs, Seps), + nth_lexeme_m(Cs1, Seps, N-1); + [Cs] -> + {Lexeme,_} = lexeme_pick(Cs, Seps, []), + Lexeme; + {nomatch,_} -> + <<>> + end. + +lexeme_skip([CP|Cs1]=Cs0, {GCs,CPs,_}=Seps) when is_integer(CP) -> + case lists:member(CP, CPs) of + true -> + [GC|Cs2] = unicode_util:gc(Cs0), + case lists:member(GC, GCs) of + true -> Cs0; + false -> lexeme_skip(Cs2, Seps) + end; + false -> + lexeme_skip(Cs1, Seps) + end; +lexeme_skip([Bin|Cont0], Seps) when is_binary(Bin) -> + case bin_search(Bin, Cont0, Seps) of + {nomatch,_} -> lexeme_skip(Cont0, Seps); + Cs -> Cs + end; +lexeme_skip(Cs0, {GCs, CPs, _} = Seps) when is_list(Cs0) -> + case unicode_util:cp(Cs0) of + [CP|Cs] -> + case lists:member(CP, CPs) of + true -> + [GC|Cs2] = unicode_util:gc(Cs0), + case lists:member(GC, GCs) of + true -> Cs0; + false -> lexeme_skip(Cs2, Seps) + end; + false -> + lexeme_skip(Cs, Seps) + end; + [] -> + [] + end; +lexeme_skip(Bin, Seps) when is_binary(Bin) -> + case bin_search(Bin, Seps) of + {nomatch,_} -> <<>>; + [Left] -> Left + end. + +find_l([Bin|Cont0], Needle) when is_binary(Bin) -> + case bin_search_str(Bin, 0, Cont0, Needle) of + {nomatch, _, Cont} -> + find_l(Cont, Needle); + {_Before, Cs, _After} -> + Cs + end; +find_l(Cs0, [C|_]=Needle) when is_list(Cs0) -> + case unicode_util:cp(Cs0) of + [C|Cs] -> + case prefix_1(Cs0, Needle) of + nomatch -> find_l(Cs, Needle); + _ -> Cs0 + end; + [_C|Cs] -> + find_l(Cs, Needle); + [] -> nomatch + end; +find_l(Bin, Needle) -> + case bin_search_str(Bin, 0, [], Needle) of + {nomatch,_,_} -> nomatch; + {_Before, [Cs], _After} -> Cs + end. + +find_r([Bin|Cont0], Needle, Res) when is_binary(Bin) -> + case bin_search_str(Bin, 0, Cont0, Needle) of + {nomatch,_,Cont} -> + find_r(Cont, Needle, Res); + {_, Cs0, _} -> + [_|Cs] = unicode_util:gc(Cs0), + find_r(Cs, Needle, Cs0) + end; +find_r(Cs0, [C|_]=Needle, Res) when is_list(Cs0) -> + case unicode_util:cp(Cs0) of + [C|Cs] -> + case prefix_1(Cs0, Needle) of + nomatch -> find_r(Cs, Needle, Res); + _ -> find_r(Cs, Needle, Cs0) + end; + [_C|Cs] -> + find_r(Cs, Needle, Res); + [] -> Res + end; +find_r(Bin, Needle, Res) -> + case bin_search_str(Bin, 0, [], Needle) of + {nomatch,_,_} -> Res; + {_Before, [Cs0], _After} -> + <<_/utf8, Cs/binary>> = Cs0, + find_r(Cs, Needle, Cs0) + end. + +%% These are used to avoid creating lists around binaries +%% might be unnecessary, is there a better solution? +btoken(Token, []) -> Token; +btoken(BinPart, [C]) when is_integer(C) -> <<C/utf8, BinPart/binary>>; +btoken(<<>>, Tkn) -> lists:reverse(Tkn); +btoken(BinPart, Cs) -> [lists:reverse(Cs),BinPart]. + +rev([B]) when is_binary(B) -> B; +rev(L) when is_list(L) -> lists:reverse(L); +rev(C) when is_integer(C) -> C. + +append(Char, <<>>) when is_integer(Char) -> [Char]; +append(Char, <<>>) when is_list(Char) -> Char; +append(Char, Bin) when is_binary(Bin) -> [Char,Bin]; +append(Char, Str) when is_integer(Char) -> [Char|Str]; +append(GC, Str) when is_list(GC) -> GC ++ Str. + +stack(Bin, []) -> Bin; +stack(<<>>, St) -> St; +stack([], St) -> St; +stack(Bin, St) -> [Bin|St]. + +add_non_empty(<<>>, L) -> L; +add_non_empty(Token, L) -> [Token|L]. + +cp_prefix(Orig, Cont) -> + case unicode_util:cp(Cont) of + [] -> Orig; + [Cp|Rest] -> cp_prefix_1(Orig, Cp, Rest) + end. + +cp_prefix_1(Orig, Until, Cont) -> + case unicode_util:cp(Orig) of + [Until|Rest] -> + case equal(Rest, Cont) of + true -> []; + false-> [Until|cp_prefix_1(Rest, Until, Cont)] + end; + [CP|Rest] -> [CP|cp_prefix_1(Rest, Until, Cont)] + end. + + +%% Binary special +bin_search(Bin, Seps) -> + bin_search(Bin, [], Seps). + +bin_search(_Bin, Cont, {[],_,_}) -> + {nomatch, Cont}; +bin_search(Bin, Cont, {Seps,_,BP}) -> + bin_search_loop(Bin, 0, BP, Cont, Seps). + +%% Need to work with [<<$a>>, <<778/utf8>>], +%% i.e. å in nfd form $a "COMBINING RING ABOVE" +%% and PREPEND characters like "ARABIC NUMBER SIGN" 1536 <<216,128>> +%% combined with other characters are currently ignored. +search_pattern(Seps) -> + CPs = search_cp(Seps), + Bin = bin_pattern(CPs), + {Seps, CPs, Bin}. + +search_cp([CP|Seps]) when is_integer(CP) -> + [CP|search_cp(Seps)]; +search_cp([Pattern|Seps]) -> + [CP|_] = unicode_util:cp(Pattern), + [CP|search_cp(Seps)]; +search_cp([]) -> []. + +bin_pattern([CP|Seps]) -> + [<<CP/utf8>>|bin_pattern(Seps)]; +bin_pattern([]) -> []. + +bin_search_loop(Bin0, Start, _, Cont, _Seps) + when byte_size(Bin0) =< Start; Start < 0 -> + {nomatch, Cont}; +bin_search_loop(Bin0, Start, BinSeps, Cont, Seps) -> + <<_:Start/binary, Bin/binary>> = Bin0, + case binary:match(Bin, BinSeps) of + nomatch -> + {nomatch,Cont}; + {Where, _CL} -> + <<_:Where/binary, Cont0/binary>> = Bin, + Cont1 = stack(Cont0, Cont), + [GC|Cont2] = unicode_util:gc(Cont1), + case lists:member(GC, Seps) of + false -> + case Cont2 of + [BinR|Cont] when is_binary(BinR) -> + Next = byte_size(Bin0) - byte_size(BinR), + bin_search_loop(Bin0, Next, BinSeps, Cont, Seps); + BinR when is_binary(BinR), Cont =:= [] -> + Next = byte_size(Bin0) - byte_size(BinR), + bin_search_loop(Bin0, Next, BinSeps, Cont, Seps); + _ -> + {nomatch, Cont2} + end; + true when is_list(Cont1) -> + Cont1; + true -> + [Cont1] + end + end. + +bin_search_inv(Bin, Cont, {[], _, _}) -> + [Bin|Cont]; +bin_search_inv(Bin, Cont, {[Sep], _, _}) -> + bin_search_inv_1([Bin|Cont], Sep); +bin_search_inv(Bin, Cont, {Seps, _, _}) -> + bin_search_inv_n([Bin|Cont], Seps). + +bin_search_inv_1([<<>>|CPs], _) -> + {nomatch, CPs}; +bin_search_inv_1(CPs = [Bin0|Cont], Sep) when is_binary(Bin0) -> + case unicode_util:gc(CPs) of + [Sep|Bin] when is_binary(Bin), Cont =:= [] -> + bin_search_inv_1([Bin], Sep); + [Sep|[Bin|Cont]=Cs] when is_binary(Bin) -> + bin_search_inv_1(Cs, Sep); + [Sep|Cs] -> + {nomatch, Cs}; + _ -> CPs + end. + +bin_search_inv_n([<<>>|CPs], _) -> + {nomatch, CPs}; +bin_search_inv_n([Bin0|Cont]=CPs, Seps) when is_binary(Bin0) -> + [C|Cs0] = unicode_util:gc(CPs), + case {lists:member(C, Seps), Cs0} of + {true, Cs} when is_binary(Cs), Cont =:= [] -> + bin_search_inv_n([Cs], Seps); + {true, [Bin|Cont]=Cs} when is_binary(Bin) -> + bin_search_inv_n(Cs, Seps); + {true, Cs} -> {nomatch, Cs}; + {false, _} -> CPs + end. + +bin_search_str(Bin0, Start, Cont, [CP|_]=SearchCPs) -> + <<_:Start/binary, Bin/binary>> = Bin0, + case binary:match(Bin, <<CP/utf8>>) of + nomatch -> {nomatch, byte_size(Bin0), Cont}; + {Where0, _} -> + Where = Start+Where0, + <<Keep:Where/binary, Cs0/binary>> = Bin0, + [GC|Cs]=unicode_util:gc(Cs0), + case prefix_1(stack(Cs0,Cont), SearchCPs) of + nomatch when is_binary(Cs) -> + KeepSz = byte_size(Bin0) - byte_size(Cs), + bin_search_str(Bin0, KeepSz, Cont, SearchCPs); + nomatch -> + {nomatch, Where, stack([GC|Cs],Cont)}; + [] -> + {Keep, [Cs0|Cont], <<>>}; + Rest -> + {Keep, [Cs0|Cont], Rest} + end + end. + + +%%--------------------------------------------------------------------------- +%% OLD lists API kept for backwards compability +%%--------------------------------------------------------------------------- + %% Robert's bit %% len(String) @@ -68,12 +1292,12 @@ len(S) -> length(S). %% equal(String1, String2) %% Test if 2 strings are equal. --spec equal(String1, String2) -> boolean() when - String1 :: string(), - String2 :: string(). +%% -spec equal(String1, String2) -> boolean() when +%% String1 :: string(), +%% String2 :: string(). -equal(S, S) -> true; -equal(_, _) -> false. +%% equal(S, S) -> true; +%% equal(_, _) -> false. %% concat(String1, String2) %% Concatenate 2 strings. @@ -127,7 +1351,7 @@ rchr([], _C, _I, L) -> L. str(S, Sub) when is_list(Sub) -> str(S, Sub, 1). str([C|S], [C|Sub], I) -> - case prefix(Sub, S) of + case l_prefix(Sub, S) of true -> I; false -> str(S, [C|Sub], I+1) end; @@ -142,16 +1366,16 @@ str([], _Sub, _I) -> 0. rstr(S, Sub) when is_list(Sub) -> rstr(S, Sub, 1, 0). rstr([C|S], [C|Sub], I, L) -> - case prefix(Sub, S) of + case l_prefix(Sub, S) of true -> rstr(S, [C|Sub], I+1, I); false -> rstr(S, [C|Sub], I+1, L) end; rstr([_|S], Sub, I, L) -> rstr(S, Sub, I+1, L); rstr([], _Sub, _I, L) -> L. -prefix([C|Pre], [C|String]) -> prefix(Pre, String); -prefix([], String) when is_list(String) -> true; -prefix(Pre, String) when is_list(Pre), is_list(String) -> false. +l_prefix([C|Pre], [C|String]) -> l_prefix(Pre, String); +l_prefix([], String) when is_list(String) -> true; +l_prefix(Pre, String) when is_list(Pre), is_list(String) -> false. %% span(String, Chars) -> Length. %% cspan(String, Chars) -> Length. @@ -229,9 +1453,9 @@ tokens(S, Seps) -> [_|_] -> [S] end; [C] -> - tokens_single_1(reverse(S), C, []); + tokens_single_1(lists:reverse(S), C, []); [_|_] -> - tokens_multiple_1(reverse(S), Seps, []) + tokens_multiple_1(lists:reverse(S), Seps, []) end. tokens_single_1([Sep|S], Sep, Toks) -> @@ -342,8 +1566,8 @@ sub_word(String, Index, Char) when is_integer(Index), is_integer(Char) -> s_word(strip(String, left, Char), Index, Char, 1, []) end. -s_word([], _, _, _,Res) -> reverse(Res); -s_word([Char|_],Index,Char,Index,Res) -> reverse(Res); +s_word([], _, _, _,Res) -> lists:reverse(Res); +s_word([Char|_],Index,Char,Index,Res) -> lists:reverse(Res); s_word([H|T],Index,Char,Index,Res) -> s_word(T,Index,Char,Index,[H|Res]); s_word([Char|T],Stop,Char,Index,Res) when Index < Stop -> s_word(strip(T,left,Char),Stop,Char,Index+1,Res); @@ -359,7 +1583,7 @@ strip(String) -> strip(String, both). -spec strip(String, Direction) -> Stripped when String :: string(), Stripped :: string(), - Direction :: left | right | both. + Direction :: 'left' | 'right' | 'both'. strip(String, left) -> strip_left(String, $\s); strip(String, right) -> strip_right(String, $\s); @@ -369,7 +1593,7 @@ strip(String, both) -> -spec strip(String, Direction, Character) -> Stripped when String :: string(), Stripped :: string(), - Direction :: left | right | both, + Direction :: 'left' | 'right' | 'both', Character :: char(). strip(String, right, Char) -> strip_right(String, Char); |