Add OCaml code generation (#24)

Also start using nailgun to speed up code generation.

  Resolves #6.

Co-authored-by: Glen Whitney <glen@studioinfinity.org>
Reviewed-on: glen/fostr#24
Co-Authored-By: Glen Whitney <glen@nobody@nowhere.net>
Co-Committed-By: Glen Whitney <glen@nobody@nowhere.net>

bin/fosgen

@@ -5,6 +5,7 @@ erro() { printf "%s\n" "$*" >&2; }
 
 ##### Set defaults:
 SUPPRESS_ERR=YES
+USE_NAILGUN=YES
 LANGUAGE=Python
 
 ##### Extract command line options:
@@ -14,18 +15,23 @@ do
     -h|--help)
       echo
       echo "Usage:"
-      echo "  fosgen [-d] [-l LANGUAGE] FILE"
+      echo "  fosgen [-d] [-j] [-l LANGUAGE] FILE"
       echo
       echo "Writes to standard output the code generated from the fostr"
       echo "program in FILE, targeting the specified LANGUAGE (which"
       echo "defaults to Python)."
       echo
       echo "The -d option writes diagnostic output to standard error."
+      echo "The -j option uses the Spoofax Sunshine JAR directly, rather"
+      echo "than via nailgun."
       exit
       ;;
     -d)
       SUPPRESS_ERR=''
       ;;
+    -j)
+      USE_NAILGUN=''
+      ;;
     -l)
       shift
       LANGUAGE="$1"
@@ -67,5 +73,17 @@ then
   exec 2>/dev/null
 fi
 
+if [[ $USE_NAILGUN ]]
+then
+  if [[ $SUPPRESS_ERR ]]
+  then
+    $BINDIR/let_sun_shine
+  else
+    $BINDIR/let_sun_shine noisy
+  fi
+  $BINDIR/ng sunshine transform -p $PROJDIR -n $LANGUAGE -i $PROGRAM
+  exit $?
+fi
+
 java -jar $SUNJAR transform -p $PROJDIR -l $PROJDIR -l $MVN_REPO -n $LANGUAGE -i $PROGRAM
 exit $?