diff -r 083bc63fcc2d Lexer.hpp
--- a/Lexer.hpp	Sat Feb 16 16:06:23 2013 +0400
+++ b/Lexer.hpp	Sat Feb 16 16:28:49 2013 +0400
@@ -99,7 +99,10 @@

             switch (ch)
             {
-            case ' ': case '\t': case '\f': case '\v':
+            case '\t':
+                throw CompilerError(*this, ErrorCode::TabsSucks);
+
+            case ' ': case '\f': case '\v':
                 return lex_impl();

             case '\n': case '\r':