can't use the exclamation marks to surround characters within a code markup, they are not allowed by the code markup, but these are allowed by the other wiki render markups.

For example, within the code markup:

• !qwerty! is not valid
• !qwerty! is valid
• 
  !qwerty! is not valid
  

To reproduce:

1. open a code block in a comment
2. type "! something..."
3. Try to save

Expected:
the comment to be saved

Actual result:
Error message, and comment not saved.

Workaround:
none, can't escape the !