From e9cb7b462b53dd2c2ccf19a948540e385d0126ba Mon Sep 17 00:00:00 2001
From: Eyal Dechter <eyaldechter@gmail.com>
Date: Wed, 19 Oct 2016 13:40:28 -0400
Subject: [PATCH] Add language extension for Prolog language.

---
 src/lang-prolog.js | 49 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)
 create mode 100644 src/lang-prolog.js

diff --git a/src/lang-prolog.js b/src/lang-prolog.js
new file mode 100644
index 00000000..34cdc159
--- /dev/null
+++ b/src/lang-prolog.js
@@ -0,0 +1,49 @@
+/**
+ * @license
+ * Copyright (C) 2016 Eyal Dechter
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * @fileoverview
+ * Registers a language handler for Prolog.
+ * @author Eyal Dechter
+ */
+
+PR['registerLangHandler'](
+    PR['createSimpleLexer'](
+        [
+            // double-quoted strings.
+            [PR['PR_STRING'], /^\"(?:[^\"\\\n\x0C\r]|\\[\s\S])*(?:\"|$)/, null, '"'],
+            // quoted atoms
+            [PR['PR_PLAIN'], /^\'(?:[^\'\\\n\x0C\r]|\\[^&])+\'?/, null, "'"],
+            // numbers
+            [PR['PR_PLAIN'], /^(?:0'.|0b[0-1]+|0o[0-7]+|0x[\da-f]+|\d+(?:\.\d+)?(?:e[+\-]?\d+)?)/i, null, '0123456789'],
+            // single-line comments begin with %
+            [PR['PR_COMMENT'], /^%[^\r\n]*/, null, '%']
+        ],
+        [
+            // atoms (don't break on underscores!)
+            [PR['PR_PLAIN'], /^[a-z][a-zA-Z0-9_]*/, null, "abcdefghijklmnopqrstuvwxyz"],
+            // block comments are delimited by /* and */
+            [PR['PR_COMMENT'], /^\/\*[\s\S]*?\*\//],
+            // directives
+            [PR['PR_KEYWORD'], /^\s*:-\s(module|use_module|export|reexport|meta_predicate|multifile|dynamic)/],
+            // variables
+            [PR['PR_TYPE'], /^[A-Z_][a-zA-Z0-9_]*/],
+            // operators
+            [PR['PR_PUNCTUATION'], /^[.,;{}:^<>=\\/+*?#!-]/]
+            
+        ]),
+    ['prolog']);