diff -r 82bfc75bcd9d -r 105c20fdeb19 editors/TextViewer.py
--- a/editors/TextViewer.py	Fri Oct 05 13:48:54 2018 +0300
+++ b/editors/TextViewer.py	Fri Oct 05 14:22:01 2018 +0300
@@ -24,6 +24,7 @@
 
 
 from __future__ import absolute_import
+from __future__ import division
 import re
 from types import *
 
@@ -893,7 +894,7 @@
                 if self.TextSyntax in ["ST", "ALL"]:
                     indent = self.Editor.GetLineIndentation(line)
                     if LineStartswith(lineText.strip(), self.BlockStartKeywords):
-                        indent = (indent / 2 + 1) * 2
+                        indent = (indent // 2 + 1) * 2
                     self.Editor.AddText("\n" + " " * indent)
                     key_handled = True
             elif key == wx.WXK_BACK:
@@ -902,7 +903,7 @@
                         indent = self.Editor.GetColumn(self.Editor.GetCurrentPos())
                         if lineText.strip() == "" and len(lineText) > 0 and indent > 0:
                             self.Editor.DelLineLeft()
-                            self.Editor.AddText(" " * ((max(0, indent - 1) / 2) * 2))
+                            self.Editor.AddText(" " * ((max(0, indent - 1) // 2) * 2))
                             key_handled = True
             if not key_handled:
                 event.Skip()