Erlang/OTP Forums

bin_replace(What, From, To) ->
    bin_replace(What, erlang:byte_size(From), What, From, To, <<>>).
   
bin_replace(WhatOrig, FromLen, What, From, To, Acc) ->
    case What of
        <<From:FromLen/binary, Other/binary>> ->
            OtherRepl = bin_replace(Other, From, To),
            <<Acc/binary, To/binary, OtherRepl/binary>>;
       
        <<Char:8, Other/binary>> ->
            bin_replace(WhatOrig, FromLen, Other, From, To, <<Acc/binary,Char>>);
       
        <<>> ->
            WhatOrig
    end.

test() ->
    Data = <<"string to replace. lalala, lalala">>,
    From = <<"lalala">>,
    To = <<"wow">>,
    Result = bin_replace(Data, From, To),
    io:format("Result=~p~n", [Result]).

bin_replace2(What, From, To) ->
    bin_replace2(What, erlang:byte_size(From), What, From, To, 0).

bin_replace2(WhatOrig, FromLen, What, From, To, Cnt) ->
    case What of
        <<From:FromLen/binary, Right/binary>> ->
            OtherRepl = bin_replace2(Right, From, To),
            <<Left:Cnt/binary,_/binary>> = WhatOrig,
            <<Left/binary, To/binary, OtherRepl/binary>>;
       
        <<_:8, Other/binary>> ->
            bin_replace2(WhatOrig, FromLen, Other, From, To, Cnt+1);
       
        <<>> ->
            WhatOrig
    end.