anchor.diff:  Text to the right of the substring to extract. This text should include
   whitespace.
   
  -If using a field as the argument, this parameter only supports the following
  +If using a field as the argument, this parameter supports only the following
   field datatypes:
   
   * <<keyword,`keyword`>>
  
positive.code: (Required, string or `null`)
  Source string. If `null`, the function returns `null`.
  
  If using a field as the argument, this parameter only supports the following
  field datatypes:
  
  * <<keyword,`keyword`>>
  
negative.code: (Required, string or `null`)
  Substring to search for. If `null`, the function returns `null`.
  
  If using a field as the argument, this parameter supports only the following
  field datatypes:
  
  * <<keyword,`keyword`>>
  