psyced/config/pikelpc.patch

This patch is necessary to apply to the Pike language source code to teach it
to not complain so much about LPC code in an #ifndef __PIKE__ part. So this
is necessary before you can try out the bin/psyked experiment to use psyced
code in pike.

You would think the preprocessor ignores anything that is not __PIKE__, but
Pike's preprocessor doesn't do that very well. To change that completely is
hard to achieve and would not be backward compatible to the custom extensions
that have been added to Pike.

Therefore this patch gently teaches Pike to deal with a few LPC specific things:

* LPC's #'lambda closure syntax is dealt as if the #' wasn't there. This means
  that the code will not trigger errors when ifdef'd out. In some cases it may
  even produce useful Pike code, as in the case of a #'callback function.

* Pike will not break on LPC's #include MACRO capability. Would be even better
  if Pike learned to support this syntax:
        #define CONFIG_PATH "/my/filesystem/is/not/like/yours/"
        #include CONFIG_PATH "myconfig.h"

* In LPC, #echo allows to quickly put a compile-time debug message into the code
  to figure out if ifdefs are properly set. Something like:
        #echo Warning: LPC version probably too old!
  This patch teaches Pike to ignore #echo statements. Would be better to
  support them.




--- preprocessor.h-orig	2007-09-04 22:56:07.002487000 +0200
+++ preprocessor.h	2007-09-16 19:15:32.179227455 +0200
@@ -1407,6 +1407,15 @@
 
     switch(data[pos])
     {
+    case '\'':
+       /*
+	* deal with LPC lambda syntax: skip the #' in #'<token>
+	* this makes function pointers syntax compatible, and allows other
+	* lambda statements to exist in an #ifndef __PIKE__ area.
+	* healthy for writing code that runs on both LPC and pike.    --lynX
+	*/
+      pos++;
+      break;
     case 'l':
       {
 	static WCHAR line_[] = { 'l', 'i', 'n', 'e' };
@@ -1568,7 +1577,12 @@
 	      }
 
 	    default:
-	      cpp_error(this, "Expected file to include.");
+		/* used to complain about LPC's macro #include syntax
+		 * even when in an #ifndef __PIKE__ zone. this is a
+		 * clear case where pike should mind its own business.
+		 * luckily an if is enough.  --lynX
+		 */
+	      if (OUTP()) cpp_error(this, "Expected file to include.");
 	      break;
 	    }
 
@@ -1799,6 +1813,7 @@
 	static WCHAR elseif_[] = { 'e', 'l', 's', 'e', 'i', 'f' };
 	static WCHAR elif_[] = { 'e', 'l', 'i', 'f' };
 	static WCHAR error_[] = { 'e', 'r', 'r', 'o', 'r' };
+	static WCHAR echo_[] = { 'e', 'c', 'h', 'o' };
 
       if(WGOBBLE2(endif_))
       {
@@ -1869,6 +1884,17 @@
 	break;
       }
 
+	/* very rudimentary implementation of the LPC #echo directive:
+	 * just skip it quietly. would be better to output it when OUTP()
+	 * but doing so looks like more work than I am willing to invest
+	 * right now..  --lynX
+	 */
+      if(WGOBBLE2(echo_)) {
+          SKIPSPACE();
+          FIND_EOL();
+	  break;
+      }
+
       if(WGOBBLE2(error_))
 	{
           ptrdiff_t foo;