diff options
| -rw-r--r-- | lib/stdlib/src/epp.erl | 118 | ||||
| -rw-r--r-- | lib/stdlib/test/epp_SUITE.erl | 91 | ||||
| -rw-r--r-- | system/doc/reference_manual/macros.xml | 4 |
3 files changed, 207 insertions, 6 deletions
diff --git a/lib/stdlib/src/epp.erl b/lib/stdlib/src/epp.erl index f55aff1e00..936c095aef 100644 --- a/lib/stdlib/src/epp.erl +++ b/lib/stdlib/src/epp.erl @@ -46,6 +46,10 @@ -type tokens() :: [erl_scan:token()]. -type used() :: {name(), argspec()}. +-type function_name_type() :: 'undefined' + | {atom(),non_neg_integer()} + | tokens(). + -define(DEFAULT_ENCODING, utf8). %% Epp state record. @@ -63,7 +67,8 @@ uses = #{} %Macro use structure :: #{name() => [{argspec(), [used()]}]}, default_encoding = ?DEFAULT_ENCODING :: source_encoding(), - pre_opened = false :: boolean() + pre_opened = false :: boolean(), + fname = [] :: function_name_type() }). %% open(Options) @@ -205,6 +210,10 @@ format_error({include,W,F}) -> io_lib:format("can't find include ~s \"~s\"", [W,F]); format_error({illegal,How,What}) -> io_lib:format("~s '-~s'", [How,What]); +format_error({illegal_function,Macro}) -> + io_lib:format("?~s can only be used within a function", [Macro]); +format_error({illegal_function_usage,Macro}) -> + io_lib:format("?~s must not begin a form", [Macro]); format_error({'NYI',What}) -> io_lib:format("not yet implemented '~s'", [What]); format_error(E) -> file:format_error(E). @@ -545,6 +554,8 @@ predef_macros(File) -> Machine = list_to_atom(erlang:system_info(machine)), Anno = line1(), Defs = [{'FILE', {none,[{string,Anno,File}]}}, + {'FUNCTION_NAME', undefined}, + {'FUNCTION_ARITY', undefined}, {'LINE', {none,[{integer,Anno,1}]}}, {'MODULE', undefined}, {'MODULE_STRING', undefined}, @@ -763,7 +774,7 @@ scan_toks([{'-',_Lh},{atom,_Lf,file}=FileToken|Toks0], From, St) -> wait_req_scan(St) end; scan_toks(Toks0, From, St) -> - case catch expand_macros(Toks0, St) of + case catch expand_macros(Toks0, St#epp{fname=Toks0}) of Toks1 when is_list(Toks1) -> epp_reply(From, {ok,Toks1}), wait_req_scan(St#epp{macs=scan_module(Toks1, St#epp.macs)}); @@ -1214,6 +1225,22 @@ get_macro_uses({M,Arity}, U) -> expand_macros([{'?',_Lq},{atom,_Lm,M}=MacT|Toks], St) -> expand_macros(MacT, M, Toks, St); %% Special macros +expand_macros([{'?',_Lq},{var,Lm,'FUNCTION_NAME'}=Token|Toks], St0) -> + St = update_fun_name(Token, St0), + case St#epp.fname of + undefined -> + [{'?',_Lq},Token]; + {Name,_} -> + [{atom,Lm,Name}] + end ++ expand_macros(Toks, St); +expand_macros([{'?',_Lq},{var,Lm,'FUNCTION_ARITY'}=Token|Toks], St0) -> + St = update_fun_name(Token, St0), + case St#epp.fname of + undefined -> + [{'?',_Lq},Token]; + {_,Arity} -> + [{integer,Lm,Arity}] + end ++ expand_macros(Toks, St); expand_macros([{'?',_Lq},{var,Lm,'LINE'}=Tok|Toks], St) -> Line = erl_scan:line(Tok), [{integer,Lm,Line}|expand_macros(Toks, St)]; @@ -1354,6 +1381,93 @@ expand_arg([A|As], Ts, _L, Rest, Bs) -> expand_arg([], Ts, L, Rest, Bs) -> expand_macro(Ts, L, Rest, Bs). +%%% +%%% Here follows support for the ?FUNCTION_NAME and ?FUNCTION_ARITY +%%% macros. Since the parser has not been run yet, we don't know the +%%% name and arity of the current function. Therefore, we will need to +%%% scan the beginning of the current form to extract the name and +%%% arity of the function. +%%% + +update_fun_name(Token, #epp{fname=Toks0}=St) when is_list(Toks0) -> + %% ?FUNCTION_NAME or ?FUNCTION_ARITY is used for the first time in + %% a function. First expand macros (except ?FUNCTION_NAME and + %% ?FUNCTION_ARITY) in the form. + + Toks1 = (catch expand_macros(Toks0, St#epp{fname=undefined})), + + %% Now extract the name and arity from the stream of tokens, and store + %% the result in the #epp{} record so we don't have to do it + %% again. + + case Toks1 of + [{atom,_,Name},{'(',_}|Toks] -> + %% This is the beginning of a function definition. + %% Scan the token stream up to the matching right + %% parenthesis and count the number of arguments. + FA = update_fun_name_1(Toks, 1, {Name,0}, St), + St#epp{fname=FA}; + [{'?',_}|_] -> + %% ?FUNCTION_NAME/?FUNCTION_ARITY used at the beginning + %% of a form. Does not make sense. + {var,_,Macro} = Token, + throw({error,loc(Token),{illegal_function_usage,Macro}}); + _ when is_list(Toks1) -> + %% Not the beginning of a function (an attribute or a + %% syntax error). + {var,_,Macro} = Token, + throw({error,loc(Token),{illegal_function,Macro}}); + _ -> + %% A macro expansion error. Return a dummy value and + %% let the caller notice and handle the error. + St#epp{fname={'_',0}} + end; +update_fun_name(_Token, St) -> + St. + +update_fun_name_1([Tok|Toks], L, FA, St) -> + case classify_token(Tok) of + comma -> + if + L =:= 1 -> + {Name,Arity} = FA, + update_fun_name_1(Toks, L, {Name,Arity+1}, St); + true -> + update_fun_name_1(Toks, L, FA, St) + end; + left -> + update_fun_name_1(Toks, L+1, FA, St); + right when L =:= 1 -> + FA; + right -> + update_fun_name_1(Toks, L-1, FA, St); + other -> + case FA of + {Name,0} -> + update_fun_name_1(Toks, L, {Name,1}, St); + {_,_} -> + update_fun_name_1(Toks, L, FA, St) + end + end; +update_fun_name_1([], _, FA, _) -> + %% Syntax error, but never mind. + FA. + +classify_token({C,_}) -> classify_token_1(C); +classify_token(_) -> other. + +classify_token_1(',') -> comma; +classify_token_1('(') -> left; +classify_token_1('{') -> left; +classify_token_1('[') -> left; +classify_token_1('<<') -> left; +classify_token_1(')') -> right; +classify_token_1('}') -> right; +classify_token_1(']') -> right; +classify_token_1('>>') -> right; +classify_token_1(_) -> other. + + %%% stringify(Ts, L) returns a list of one token: a string which when %%% tokenized would yield the token list Ts. diff --git a/lib/stdlib/test/epp_SUITE.erl b/lib/stdlib/test/epp_SUITE.erl index 955b482313..bd8939ccca 100644 --- a/lib/stdlib/test/epp_SUITE.erl +++ b/lib/stdlib/test/epp_SUITE.erl @@ -27,7 +27,7 @@ pmod/1, not_circular/1, skip_header/1, otp_6277/1, otp_7702/1, otp_8130/1, overload_mac/1, otp_8388/1, otp_8470/1, otp_8562/1, otp_8665/1, otp_8911/1, otp_10302/1, otp_10820/1, - otp_11728/1, encoding/1, extends/1]). + otp_11728/1, encoding/1, extends/1, function_macro/1]). -export([epp_parse_erl_form/2]). @@ -70,7 +70,7 @@ all() -> not_circular, skip_header, otp_6277, otp_7702, otp_8130, overload_mac, otp_8388, otp_8470, otp_8562, otp_8665, otp_8911, otp_10302, otp_10820, otp_11728, - encoding, extends]. + encoding, extends, function_macro]. groups() -> [{upcase_mac, [], [upcase_mac_1, upcase_mac_2]}, @@ -843,8 +843,9 @@ otp_8130(Config) when is_list(Config) -> "t() -> ?a.\n"), ?line {ok,Epp} = epp:open(File, []), PreDefMacs = macs(Epp), - ['BASE_MODULE','BASE_MODULE_STRING','BEAM','FILE','LINE', - 'MACHINE','MODULE','MODULE_STRING'] = PreDefMacs, + ['BASE_MODULE','BASE_MODULE_STRING','BEAM','FILE', + 'FUNCTION_ARITY','FUNCTION_NAME', + 'LINE','MACHINE','MODULE','MODULE_STRING'] = PreDefMacs, ?line {ok,[{'-',_},{atom,_,file}|_]} = epp:scan_erl_form(Epp), ?line {ok,[{'-',_},{atom,_,module}|_]} = epp:scan_erl_form(Epp), ?line {ok,[{atom,_,t}|_]} = epp:scan_erl_form(Epp), @@ -1491,6 +1492,88 @@ extends(Config) -> [] = run(Config, Ts), ok. +function_macro(Config) -> + Cs = [{f_c1, + <<"-define(FUNCTION_NAME, a).\n" + "-define(FUNCTION_ARITY, a).\n" + "-define(FS,\n" + " atom_to_list(?FUNCTION_NAME) ++ \"/\" ++\n" + " integer_to_list(?FUNCTION_ARITY)).\n" + "-attr({f,?FUNCTION_NAME}).\n" + "-attr2(?FS).\n" + "-file(?FUNCTION_ARITY, 1).\n" + "f1() ?FUNCTION_NAME/?FUNCTION_ARITY.\n" + "f2(?FUNCTION_NAME.\n">>, + {errors,[{1,epp,{redefine_predef,'FUNCTION_NAME'}}, + {2,epp,{redefine_predef,'FUNCTION_ARITY'}}, + {6,epp,{illegal_function,'FUNCTION_NAME'}}, + {7,epp,{illegal_function,'FUNCTION_NAME'}}, + {8,epp,{illegal_function,'FUNCTION_ARITY'}}, + {9,erl_parse,["syntax error before: ","f1"]}, + {10,erl_parse,["syntax error before: ","'.'"]}], + []}}, + + {f_c2, + <<"a({a) -> ?FUNCTION_NAME.\n" + "b(}{) -> ?FUNCTION_ARITY.\n" + "c(?FUNCTION_NAME, ?not_defined) -> ok.\n">>, + {errors,[{1,erl_parse,["syntax error before: ","')'"]}, + {2,erl_parse,["syntax error before: ","'}'"]}, + {3,epp,{undefined,not_defined,none}}], + []}}, + + {f_c3, + <<"?FUNCTION_NAME() -> ok.\n" + "?FUNCTION_ARITY() -> ok.\n">>, + {errors,[{1,epp,{illegal_function_usage,'FUNCTION_NAME'}}, + {2,epp,{illegal_function_usage,'FUNCTION_ARITY'}}], + []}} + ], + + [] = compile(Config, Cs), + + Ts = [{f_1, + <<"t() -> {a,0} = a(), {b,1} = b(1), {c,2} = c(1, 2),\n" + " {d,1} = d({d,1}), {foo,1} = foo(foo), ok.\n" + "a() -> {?FUNCTION_NAME,?FUNCTION_ARITY}.\n" + "b(_) -> {?FUNCTION_NAME,?FUNCTION_ARITY}.\n" + "c(_, (_)) -> {?FUNCTION_NAME,?FUNCTION_ARITY}.\n" + "d({?FUNCTION_NAME,?FUNCTION_ARITY}=F) -> F.\n" + "-define(FOO, foo).\n" + "?FOO(?FOO) -> {?FUNCTION_NAME,?FUNCTION_ARITY}.\n">>, + ok}, + + {f_2, + <<"t() ->\n" + " A = {a,[<<0:24>>,#{a=>1,b=>2}]},\n" + " 1 = a(A),\n" + " ok.\n" + "a({a,[<<_,_,_>>,#{a:=1,b:=2}]}) -> ?FUNCTION_ARITY.\n">>, + ok}, + + {f_3, + <<"-define(FS,\n" + " atom_to_list(?FUNCTION_NAME) ++ \"/\" ++\n" + " integer_to_list(?FUNCTION_ARITY)).\n" + "t() ->\n" + " {t,0} = {?FUNCTION_NAME,?FUNCTION_ARITY},\n" + " \"t/0\" = ?FS,\n" + " ok.\n">>, + ok}, + + {f_4, + <<"-define(__, _, _).\n" + "-define(FF, ?FUNCTION_NAME, ?FUNCTION_ARITY).\n" + "a(?__) -> 2 = ?FUNCTION_ARITY.\n" + "b(?FUNCTION_ARITY, ?__) -> ok.\n" + "c(?FF) -> ok.\n" + "t() -> a(1, 2), b(3, 1, 2), c(c, 2), ok.\n">>, + ok} + ], + [] = run(Config, Ts), + + ok. + check(Config, Tests) -> eval_tests(Config, fun check_test/2, Tests). diff --git a/system/doc/reference_manual/macros.xml b/system/doc/reference_manual/macros.xml index 3b1f72e5d6..42ea639b54 100644 --- a/system/doc/reference_manual/macros.xml +++ b/system/doc/reference_manual/macros.xml @@ -146,6 +146,10 @@ bar(X) -> <item>The current line number.</item> <tag><c>?MACHINE</c>.</tag> <item>The machine name, <c>'BEAM'</c>.</item> + <tag><c>?FUNCTION_NAME</c></tag> + <item>The name of the current function.</item> + <tag><c>?FUNCTION_ARITY</c></tag> + <item>The arity (number of arguments) for the current function.</item> </taglist> </section> |