更新时间:2021-10-10 22:02:50
注意:目前Elixir版本还不稳定,代码调整较大,本文随时失效
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-module(elixir). ...... start_cli() -> application:start(?MODULE),
%% start_cli() --> [ "+compile" , "m.ex" ]
'Elixir.Kernel.CLI' :main(init:get_plain_arguments()).
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defmodule Kernel.CLI do
...... if files != [] do
wrapper fn ->
Code.compiler_options(config.compiler_options)
Kernel.ParallelCompiler.files_to_path(files, config.output,
each_file: fn file -> if config.verbose_compile do IO.puts "Compiled #{file}" end end)
end
else
{ :error, "--compile : No files matched patterns #{Enum.join(patterns, " , ")}" }
end
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defmodule Kernel.ParallelCompiler do
..... try do
if output do
:elixir_compiler.file_to_path(h, output)
else
:elixir_compiler.file(h)
end
parent <- { :compiled, self(), h }
catch
kind, reason ->
parent <- { :failure, self(), kind, reason, System.stacktrace }
end
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-module(elixir_compiler). file(Relative) when is_binary(Relative) -> File = filename:absname(Relative),
{ ok, Bin } = file:read_file(File),
string (elixir_utils:characters_to_list(Bin), File).
string (Contents, File) when is_list(Contents), is_binary(File) ->
Forms = elixir_translator: 'forms!' (Contents, 1, File, []),
quoted(Forms, File).
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[{defmodule, [{line,1}],
[{ '__aliases__' ,[{line,1}],[ 'Math' ]},
[{ do ,
{def,[{line,2}],[{sum,[{line,2}],[{a,[{line,2}],nil},{b,[{line,2}],nil}]},
[{ do ,{ '__block__' ,[],[
{ '=' ,[{line,3}],[{a,[{line,3}],nil},123]},
{ '=' ,[{line,4}],[{a,[{line,4}],nil},2365]},
{ '+' ,[{line,5}],[
{a,[{line,5}],nil},{b,[{line,5}],nil}]}
]}}]]}}]]}]
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-record(elixir_scope, { context=nil, %% can be assign, guards or nil
extra=nil, %% extra information about the context, like fn_match for fns
noname= false , %% when true , don't add new names (used by try )
super= false , %% when true , it means super was invoked
caller= false , %% when true , it means caller was invoked
module=nil, %% the current module
function=nil, %% the current function
vars=[], %% a dict of defined variables and their alias
backup_vars=nil, %% a copy of vars to be used on ^ var
temp_vars=nil, %% a set of all variables defined in a particular assign
clause_vars=nil, %% a dict of all variables defined in a particular clause
extra_guards=nil, %% extra guards from args expansion
counter=[], %% a counter for the variables defined
local=nil, %% the scope to evaluate local functions against
context_modules=[], %% modules defined in the current context
macro_aliases=[], %% keep aliases defined inside a macro
macro_counter=0, %% macros expansions counter
lexical_tracker=nil, %% holds the lexical tracker pid
aliases, %% an orddict with aliases by new -> old names
file, %% the current scope filename
requires, %% a set with modules required
macros, %% a list with macros imported from module
functions %% a list with functions imported from module
}). |
quoted方法最近的变化是使用elixir_lexical:run包装了一下,之前的版本简单直接,可以先看一下:
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quoted(Forms, File) when is_binary(File) -> Previous = get (elixir_compiled),
% M:elixir_compiler Previous undefined try
put(elixir_compiled, []),
eval_forms(Forms, 1, [], elixir:scope_for_eval([{file,File}])),
lists:reverse( get (elixir_compiled))
after
put(elixir_compiled, Previous)
end.
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现在quoted是这样的:
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quoted(Forms, File) when is_binary(File) -> Previous = get (elixir_compiled),
try
put(elixir_compiled, []),
elixir_lexical:run(File, fun
(Pid) ->
Scope = elixir:scope_for_eval([{file,File}]),
eval_forms(Forms, 1, [], Scope#elixir_scope{lexical_tracker=Pid})
end),
lists:reverse( get (elixir_compiled))
after
put(elixir_compiled, Previous)
end.
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quoted方法里面我们需要重点关注的是eval_forms方法,在这个方法里面完成了Elixir AST到Erlang AST转换,Elixir表达式通过 elixir_translator:translate被翻译成对应的Erlang Abstract Format.之后eval_mod(Fun, Exprs, Line, File, Module, Vars)完成对表达式和代码其它部分(比如attribute,等等)进行组合.
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eval_forms(Forms, Line, Vars, S) -> { Module, I } = retrieve_module_name(),
{ Exprs, FS } = elixir_translator:translate(Forms, S),
Fun = eval_fun(S#elixir_scope.module),
Form = eval_mod(Fun, Exprs, Line, S#elixir_scope.file, Module, Vars),
Args = list_to_tuple([V || { _, V } <- Vars]),
%% Pass { native, false } to speed up bootstrap
%% process when native is set to true
{ module(Form, S#elixir_scope.file, [{native, false }], true ,
fun(_, Binary) ->
Res = Module:Fun(Args),
code:delete(Module),
%% If we have labeled locals, anonymous functions
%% were created and therefore we cannot ditch the
%% module
case beam_lib:chunks(Binary, [labeled_locals]) of
{ ok, { _, [{ labeled_locals, []}] } } ->
code:purge(Module),
return_module_name(I);
_ ->
ok
end,
Res
end), FS }.
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最后完成编译和加载的重头戏就在module(Forms, File, Opts, Callback)方法了:
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%% Compile the module by forms based on the scope information
%% executes the callback in case of success. This automatically
%% handles errors and warnings. Used by this module and elixir_module.
module(Forms, File, Opts, Callback) -> DebugInfo = (get_opt(debug_info) == true ) orelse lists:member(debug_info, Opts),
Final =
if DebugInfo -> [debug_info];
true -> []
end,
module(Forms, File, Final, false , Callback).
module(Forms, File, RawOptions, Bootstrap, Callback) when is_binary(File), is_list(Forms), is_list(RawOptions), is_boolean(Bootstrap), is_function(Callback) ->
{ Options, SkipNative } = compile_opts(Forms, RawOptions),
Listname = elixir_utils:characters_to_list(File),
case compile:noenv_forms([no_auto_import()|Forms], [ return ,{source,Listname}|Options]) of
{ok, ModuleName, Binary, RawWarnings} ->
Warnings = case SkipNative of
true -> [{?MODULE,[{0,?MODULE,{skip_native,ModuleName}}]}|RawWarnings];
false -> RawWarnings
end,
format_warnings(Bootstrap, Warnings),
%%%% ModuleName : 'Elixir.Math' ListName: "/data2/elixir/m.ex"
code:load_binary(ModuleName, Listname, Binary),
Callback(ModuleName, Binary);
{error, Errors, Warnings} ->
format_warnings(Bootstrap, Warnings),
format_errors(Errors)
end.
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到这里编译的流程已经走完,附上几个可能会用到的资料,首先是elixir_parser:parse(Tokens)的代码,你可能会奇怪这个模块的代码在哪里?这个是通过elixir_parser.yrl编译自动生成的模块,你可以使用下面的方法拿到它的代码:
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Eshell V5.10.2 (abort with ^G) 1> {ok,{_,[{abstract_code,{_,AC}}]}} = beam_lib:chunks( "elixir_parser" ,[abstract_code]).
{ok,{elixir_parser, [{abstract_code, ........ {...}|...]}}]}} 2> Dump= fun(Content)-> file:write_file( "/data/dump.data" , io_lib:fwrite( "~ts.\n" , [Content])) end.
#Fun<erl_eval.6.80484245> 3> Dump(erl_prettypr:format(erl_syntax:form_list(AC))). ok 4> |
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本文转自博客园坚强2002的博客,原文链接:
http://www.cnblogs.com/me-sa/p/elixir_compile_step.html如需转载请自行联系原博主。