Allow placement on left (thanks to Miguel Aguilar Molina).

README.md

@@ -81,9 +81,10 @@ Configures whether to show the comment (aka. weather condition text, e.g. "Windy
 
 #### Position in Panel (optional, center by default)
 
-The position of this GNOME Shell extension in the panel can be configured to either 'center' or 'right' (requires restart of GNOME Shell).
+The position of this GNOME Shell extension in the panel can be configured to either 'left', 'center' or 'right' (requires restart of GNOME Shell).
 
     gsettings set org.gnome.shell.extensions.weather position-in-panel center
+    gsettings set org.gnome.shell.extensions.weather position-in-panel left
     gsettings set org.gnome.shell.extensions.weather position-in-panel right
 
 #### Restart GNOME Shell

src/extension.js

@@ -62,7 +62,8 @@ const WeatherUnits = {
 }
 const WeatherPosition = {
     CENTER: 0,
-    RIGHT: 1
+    RIGHT: 1,
+    LEFT: 2
 }
 
 function WeatherMenuButton() {
@@ -138,12 +139,17 @@ WeatherMenuButton.prototype = {
             topBox.add_actor(this._weatherInfo);
         this.actor.set_child(topBox);
 
+        let children = null;
         switch (this._position_in_panel) {
+            case WeatherPosition.LEFT:
+                children = Main.panel._leftBox.get_children();
+                Main.panel._leftBox.insert_actor (this.actor, children.length-1);
+                break;
             case WeatherPosition.CENTER:
                 Main.panel._centerBox.add(this.actor, { y_fill: true });
                 break;
             case WeatherPosition.RIGHT:
-                let children = Main.panel._rightBox.get_children();
+                children = Main.panel._rightBox.get_children();
                 Main.panel._rightBox.insert_actor(this.actor, children.length-1);
                 break;
         }

src/org.gnome.shell.extensions.weather.gschema.xml.in

@@ -6,6 +6,7 @@
   <enum id="org.gnome.shell.extensions.weather.position">
     <value nick="center" value="0" />
     <value nick="right" value="1" />
+    <value nick="left" value="2"  />
   </enum>
   <schema id="org.gnome.shell.extensions.weather" path="/org/gnome/shell/extensions/weather/">
     <key name="unit" enum="org.gnome.shell.extensions.weather.unit">
@@ -46,7 +47,7 @@
     <key name="position-in-panel" enum="org.gnome.shell.extensions.weather.position">
       <default>'center'</default>
       <_summary>Position in panel</_summary>
-      <_description>Set the position of this GNOME Shell extension in the panel to either 'center' or 'right' (requires restart).</_description>
+      <_description>Set the position of this GNOME Shell extension in the panel to either 'center', 'left' or 'right' (requires restart).</_description>
     </key>
   </schema>
 </schemalist>