[seed] Add lang.js from GJS modules

[Robert Carr <racarr src gnome org>]

commit 7db832dd1425dc2cab8124af945aca386c6fd086
Author: Robert Carr <racarr svn gnome org>
Date:   Sat May 9 21:27:19 2009 -0400

    Add lang.js from GJS modules
---
 modules/dbus/Makefile.am |    2 +-
 modules/dbus/lang.js     |  112 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 113 insertions(+), 1 deletions(-)

diff --git a/modules/dbus/Makefile.am b/modules/dbus/Makefile.am
index 5b8804f..7dcffa6 100644
--- a/modules/dbus/Makefile.am
+++ b/modules/dbus/Makefile.am
@@ -1,7 +1,7 @@
 if BUILD_DBUS_MODULE
 
 moduledir = ${seeddir}/share/seed
-module_DATA = dbus.js
+module_DATA = dbus.js lang.js
 
 seedlibdir = ${exec_prefix}/lib/seed
 
diff --git a/modules/dbus/lang.js b/modules/dbus/lang.js
new file mode 100644
index 0000000..baa00fc
--- /dev/null
+++ b/modules/dbus/lang.js
@@ -0,0 +1,112 @@
+// Copyright (c) 2008  litl, LLC
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+
+// Utilities that are "meta-language" things like manipulating object props
+
+function countProperties(obj) {
+    let count = 0;
+    for (let property in obj) {
+        count += 1;
+    }
+    return count;
+}
+
+function _copyProperty(source, dest, property) {
+    let getterFunc = source.__lookupGetter__(property);
+    let setterFunc = source.__lookupSetter__(property);
+
+    if (getterFunc) {
+        dest.__defineGetter__(property, getterFunc);
+    }
+
+    if (setterFunc) {
+        dest.__defineSetter__(property, setterFunc);
+    }
+
+    if (!setterFunc && !getterFunc) {
+        dest[property] = source[property];
+    }
+}
+
+function copyProperties(source, dest) {
+    for (let property in source) {
+        _copyProperty(source, dest, property);
+    }
+}
+
+function copyPublicProperties(source, dest) {
+    for (let property in source) {
+        if (typeof(property) == 'string' &&
+            property.substring(0, 1) == '_') {
+            continue;
+        } else {
+            _copyProperty(source, dest, property);
+        }
+    }
+}
+
+function copyPropertiesNoOverwrite(source, dest) {
+    for (let property in source) {
+        if (!(property in dest)) {
+            _copyProperty(source, dest, property);
+        }
+    }
+}
+
+function removeNullProperties(obj) {
+    for (let property in obj) {
+        if (obj[property] == null)
+            delete obj[property];
+        else if (typeof(obj[property]) == 'object')
+            removeNullProperties(obj[property]);
+    }
+}
+
+/**
+ * Binds obj to callback. Makes it possible to refer to "obj"
+ * using this within the callback.
+ * @param {object} obj the object to bind
+ * @param {function} callback callback to bind obj in
+ * @param arguments additional arguments to the callback
+ * @returns: a new callback
+ * @type: function
+ */
+function bind(obj, callback) {
+    let me = obj;
+    let bindArguments = Array.prototype.slice.call(arguments, 2);
+
+    if (typeof(obj) != 'object') {
+        throw new Error(
+            "first argument to Lang.bind() must be an object, not " +
+                typeof(obj));
+    }
+
+    if (typeof(callback) != 'function') {
+        throw new Error(
+            "second argument to Lang.bind() must be a function, not " +
+                typeof(callback));
+    }
+
+    return function() {
+        let args = Array.prototype.slice.call(arguments);
+        args = args.concat(bindArguments);
+        return callback.apply(me, args);
+    };
+}