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Diffstat (limited to 'lib/stdlib/src/binary.erl')
| -rw-r--r-- | lib/stdlib/src/binary.erl | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/lib/stdlib/src/binary.erl b/lib/stdlib/src/binary.erl new file mode 100644 index 0000000000..f6489788b2 --- /dev/null +++ b/lib/stdlib/src/binary.erl @@ -0,0 +1,177 @@ +%% +%% %CopyrightBegin% +%% +%% Copyright Ericsson AB 2010. 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(binary). +%% +%% The following functions implemented as BIF's +%% binary:compile_pattern/1 +%% binary:match/{2,3} +%% binary:matches/{2,3} +%% binary:longest_common_prefix/1 +%% binary:longest_common_suffix/1 +%% binary:first/1 +%% binary:last/1 +%% binary:at/2 +%% binary:part/{2,3} +%% binary:bin_to_list/{1,2,3} +%% binary:list_to_bin/1 +%% binary:copy/{1,2} +%% binary:referenced_byte_size/1 +%% binary:decode_unsigned/{1,2} +%% - Not yet: +%% +%% Implemented in this module: +-export([split/2,split/3,replace/3,replace/4]). + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%% split +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +split(H,N) -> + split(H,N,[]). +split(Haystack,Needles,Options) -> + try + {Part,Global,Trim} = get_opts_split(Options,{no,false,false}), + Moptlist = case Part of + no -> + []; + {A,B} -> + [{scope,{A,B}}] + end, + MList = if + Global -> + binary:matches(Haystack,Needles,Moptlist); + true -> + case binary:match(Haystack,Needles,Moptlist) of + nomatch -> []; + Match -> [Match] + end + end, + do_split(Haystack,MList,0,Trim) + catch + _:_ -> + erlang:error(badarg) + end. + +do_split(H,[],N,true) when N >= byte_size(H) -> + []; +do_split(H,[],N,_) -> + [binary:part(H,{N,byte_size(H)-N})]; +do_split(H,[{A,B}|T],N,Trim) -> + case binary:part(H,{N,A-N}) of + <<>> -> + Rest = do_split(H,T,A+B,Trim), + case {Trim, Rest} of + {true,[]} -> + []; + _ -> + [<<>> | Rest] + end; + Oth -> + [Oth | do_split(H,T,A+B,Trim)] + end. + + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%% replace +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +replace(H,N,R) -> + replace(H,N,R,[]). +replace(Haystack,Needles,Replacement,Options) -> + try + true = is_binary(Replacement), % Make badarg instead of function clause + {Part,Global,Insert} = get_opts_replace(Options,{no,false,[]}), + Moptlist = case Part of + no -> + []; + {A,B} -> + [{scope,{A,B}}] + end, + MList = if + Global -> + binary:matches(Haystack,Needles,Moptlist); + true -> + case binary:match(Haystack,Needles,Moptlist) of + nomatch -> []; + Match -> [Match] + end + end, + ReplList = case Insert of + [] -> + Replacement; + Y when is_integer(Y) -> + splitat(Replacement,0,[Y]); + Li when is_list(Li) -> + splitat(Replacement,0,lists:sort(Li)) + end, + erlang:iolist_to_binary(do_replace(Haystack,MList,ReplList,0)) + catch + _:_ -> + erlang:error(badarg) + end. + + +do_replace(H,[],_,N) -> + [binary:part(H,{N,byte_size(H)-N})]; +do_replace(H,[{A,B}|T],Replacement,N) -> + [binary:part(H,{N,A-N}), + if + is_list(Replacement) -> + do_insert(Replacement, binary:part(H,{A,B})); + true -> + Replacement + end + | do_replace(H,T,Replacement,A+B)]. + +do_insert([X],_) -> + [X]; +do_insert([H|T],R) -> + [H,R|do_insert(T,R)]. + +splitat(H,N,[]) -> + [binary:part(H,{N,byte_size(H)-N})]; +splitat(H,N,[I|T]) -> + [binary:part(H,{N,I-N})|splitat(H,I,T)]. + + + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%% Simple helper functions +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +get_opts_split([],{Part,Global,Trim}) -> + {Part,Global,Trim}; +get_opts_split([{scope,{A,B}} | T],{_Part,Global,Trim}) -> + get_opts_split(T,{{A,B},Global,Trim}); +get_opts_split([global | T],{Part,_Global,Trim}) -> + get_opts_split(T,{Part,true,Trim}); +get_opts_split([trim | T],{Part,Global,_Trim}) -> + get_opts_split(T,{Part,Global,true}); +get_opts_split(_,_) -> + throw(badopt). + +get_opts_replace([],{Part,Global,Insert}) -> + {Part,Global,Insert}; +get_opts_replace([{scope,{A,B}} | T],{_Part,Global,Insert}) -> + get_opts_replace(T,{{A,B},Global,Insert}); +get_opts_replace([global | T],{Part,_Global,Insert}) -> + get_opts_replace(T,{Part,true,Insert}); +get_opts_replace([{insert_replaced,N} | T],{Part,Global,_Insert}) -> + get_opts_replace(T,{Part,Global,N}); +get_opts_replace(_,_) -> + throw(badopt). + |