[erlang-questions] idea: using erlc for more file types

[Vlad Dumitrescu]

Hi all,

 ("idea" was the closest matching tag, sometimes it's difficult to
know what's appropriate)

I would need to process files in Erlang that are not in the set that
is handled by erlc, but it would be very handy if they were. I think
then that it's not an earth-shattering suggestion that erlc should be
able to handle other file types.

A way to solve that would be by adding a command-line parameter
  -compiler mymodule:myfunction
and use the specified function as entry point for the compiler proper.

A patch is attached (but of course, better and cleaner solutions may exist).

best regards,
Vlad

----------------------

Index: erts/etc/common/erlc.c
===================================================================
--- erts/etc/common/erlc.c	(revision 18)
+++ erts/etc/common/erlc.c	(working copy)
@@ -187,6 +187,9 @@
 		PUSH2("@output_type", output_type);
 		break;
 	    case 'c':		/* Allowed for compatibility with 'erl'. */
+		if (strcmp(argv[1], "-compiler") == 0) {
+		    PUSH2("@compiler", process_opt(&argc, &argv, 0));
+		} else
 		if (strcmp(argv[1], "-compile") != 0)
 		    goto error;
 		break;
Index: lib/stdlib/include/erl_compile.hrl
===================================================================
--- lib/stdlib/include/erl_compile.hrl	(revision 18)
+++ lib/stdlib/include/erl_compile.hrl	(working copy)
@@ -36,7 +36,8 @@
 	  specific=[],				% Compiler specific options.
 	  outfile="",				% Name of output file (internal
 						% use in erl_compile.erl).
-	  cwd					% Current working directory
+	  cwd,					% Current working directory
 						% for erlc.
+	  compiler
 	 }).

Index: lib/stdlib/src/erl_compile.erl
===================================================================
--- lib/stdlib/src/erl_compile.erl	(revision 18)
+++ lib/stdlib/src/erl_compile.erl	(working copy)
@@ -26,22 +26,24 @@

 %% Mapping from extension to {M,F} to run the correct compiler.

-compiler(".erl") ->    {compile,         compile};
-compiler(".S") ->      {compile,         compile_asm};
-compiler(".beam") ->   {compile,         compile_beam};
-compiler(".core") ->   {compile,         compile_core};
-compiler(".mib") ->    {snmpc,           compile};
-compiler(".bin") ->    {snmpc,           mib_to_hrl};
-compiler(".yrl") ->    {yecc,            compile};
-compiler(".script") -> {systools,        script2boot};
-compiler(".rel") ->    {systools,        compile_rel};
-compiler(".idl") ->    {ic,              compile};
-compiler(".asn1") ->   {asn1ct,          compile_asn1};
-compiler(".asn") ->    {asn1ct,          compile_asn};
-compiler(".py") ->     {asn1ct,          compile_py};
-compiler(".xml") ->    {xmerl_scan,      process};
-compiler(_) ->         no.
+compiler(".erl", _) ->    {compile,         compile};
+compiler(".S", _) ->      {compile,         compile_asm};
+compiler(".beam", _) ->   {compile,         compile_beam};
+compiler(".core", _) ->   {compile,         compile_core};
+compiler(".mib", _) ->    {snmpc,           compile};
+compiler(".bin", _) ->    {snmpc,           mib_to_hrl};
+compiler(".yrl", _) ->    {yecc,            compile};
+compiler(".script", _) -> {systools,        script2boot};
+compiler(".rel", _) ->    {systools,        compile_rel};
+compiler(".idl", _) ->    {ic,              compile};
+compiler(".asn1", _) ->   {asn1ct,          compile_asn1};
+compiler(".asn", _) ->    {asn1ct,          compile_asn};
+compiler(".py", _) ->     {asn1ct,          compile_py};
+compiler(".xml", _) ->    {xmerl_scan,      process};
+compiler(_, #options{compiler=C}) -> C;
+compiler(_, _) ->         no.

+
 %% Entry from command line.

 compile_cmdline(List) ->
@@ -130,8 +132,16 @@
     compile1(Rest, Cwd, Opts#options{output_type=OutputType});
 compile1(['@files'|Rest], Cwd, Opts) ->
     Includes = lists:reverse(Opts#options.includes),
-    compile2(Rest, Cwd, Opts#options{includes=Includes}).
+    compile2(Rest, Cwd, Opts#options{includes=Includes});
+compile1(['@compiler', MF|Rest], Cwd, Opts) ->
+    case string:tokens(MF, ":") of
+	  [M, F] ->
+		compile2(Rest, Cwd, Opts#options{compiler={make_term(M), make_term(F)}});
+	  _ ->
+		compile2(Rest, Cwd, Opts)
+	end.

+
 compile2(Files, Cwd, Opts) ->
     case {Opts#options.outfile, length(Files)} of
 	{"", _} ->