diff --git a/spec/atom/command-interpreter-spec.coffee b/spec/atom/command-interpreter-spec.coffee
index 894bcb931..22cb97874 100644
--- a/spec/atom/command-interpreter-spec.coffee
+++ b/spec/atom/command-interpreter-spec.coffee
@@ -16,11 +16,6 @@ describe "CommandInterpreter", ->
         interpreter.eval(editor, '4')
         expect(editor.selection.getBufferRange()).toEqual [[3, 0], [4, 0]]
 
-    describe "an address range with two line addresses", ->
-      it "selects the given lines", ->
-        interpreter.eval(editor, '4,7')
-        expect(editor.selection.getBufferRange()).toEqual [[3, 0], [7, 0]]
-
     describe "0", ->
       it "selects the zero-length string at the start of the file", ->
         interpreter.eval(editor, '0')
@@ -37,6 +32,28 @@ describe "CommandInterpreter", ->
         interpreter.eval(editor, '1,$')
         expect(editor.selection.getBufferRange()).toEqual [[0,0], [12,2]]
 
+    describe "address range", ->
+      describe "when two addresses are specified", ->
+        it "selects from the begining of the left address to the end of the right address", ->
+          interpreter.eval(editor, '4,7')
+          expect(editor.selection.getBufferRange()).toEqual [[3, 0], [7, 0]]
+
+      describe "when the left address is unspecified", ->
+        it "selects from the begining of buffer to the end of the right address", ->
+          interpreter.eval(editor, ',7')
+          expect(editor.selection.getBufferRange()).toEqual [[0, 0], [7, 0]]
+
+      describe "when the right address is unspecified", ->
+        it "selects from the begining of left address to the end file", ->
+          interpreter.eval(editor, '4,')
+          expect(editor.selection.getBufferRange()).toEqual [[3, 0], [12, 2]]
+
+      describe "when the neither address is specified", ->
+        it "selects the entire file", ->
+          interpreter.eval(editor, ',')
+          expect(editor.selection.getBufferRange()).toEqual [[0, 0], [12, 2]]
+
+
   describe "substitution", ->
     it "does nothing if there are no matches", ->
       editor.selection.setBufferRange([[6, 0], [6, 44]])
diff --git a/src/atom/commands.pegjs b/src/atom/commands.pegjs
index 76eae388d..19c531053 100644
--- a/src/atom/commands.pegjs
+++ b/src/atom/commands.pegjs
@@ -16,7 +16,11 @@ start
 address = addressRange / primitiveAddress
 
 addressRange
-  = start:primitiveAddress _ ',' _ end:address { return new AddressRange(start, end) }
+  = start:primitiveAddress? _ ',' _ end:address? {
+    if (!start) start = new LineAddress(0)
+    if (!end) end = new EofAddress()
+    return new AddressRange(start, end)
+  }
 
 primitiveAddress
   = lineNumber:integer { return new LineAddress(lineNumber) }