erlang file_for_each 

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%%============================================%%
%% 对文件进行遍历，以行为单位进行输出，没一行构成一个列表元素，
%% 最终拼成一个列表。 edit code by lgh
%%============================================%%

-module(for_each_file).
% -compile([export_all]).
-export([start/1]).

start(FileName) ->
    {ok, Bin} = file:read_file(FileName),
    L = binary_to_list(Bin),
    io:format("The File Prototype is -> ~p~n",[L]),   %% 文件原型列表
    find_word(L, []).

find_word([], Acc) ->
    io:format("The result is -> ~p~n",[lists:reverse(Acc)]),  %% 最终效果列表
    ok;

find_word(L, Acc) ->
    {Word, L0} = for_each_word(L, []),
    Acc0 = [Word | Acc],
    find_word(L0, Acc0).

%% 遇到换行符，返回单词和剩余的列表。
for_each_word([$\n | T], L) ->
    {lists:reverse(L), T};

for_each_word([H|T], L) ->
    for_each_word(T, [H|L]);

for_each_word([], L) ->
    {lists:reverse(L), []}.