ability to replace text

couleur.py

@@ -36,6 +36,7 @@ class modifiers:
     underline = ansify(4)
     inverse = ansify(7)
     strikethrough = ansify(9)
+    up = '\r\033[A'
 
     class off:
         bold = ansify(22)
@@ -119,7 +120,7 @@ class Shell(object):
             parts.append("\n")
 
         string = "".join(parts)
-        return lambda z: sys.stdout.write(string % z)
+        return lambda z, replace=False: sys.stdout.write((replace and modifiers.up or '') + string % z)
 
 
     def __getattr__(self, attr):

test_couleur.py

@@ -118,3 +118,11 @@ def test_bold_inline():
     sh.print_bold_normal_on_red("World")
     assert_stdout('\033[44m\033[1m\033[39mHello\033[0m\033[41m\033[1m\033[39mWorld\033[0m')
 
+@with_setup(prepare_stdout)
+def test_update_shell():
+    "updating the shell, replacing the last output"
+    sh = Shell(indent=6)
+    sh.print_yellow("Yellow")
+    sh.indent()
+    sh.print_red("Red", True)
+    assert_stdout('\033[33mYellow\033[0m\r\033[A      \033[31mRed\033[0m')