History for CurrentBehavior

??changed:
-
Python Methods Current Behavior

  - uses GuardedBlock for security

  - copies methods from !DocumentTemplate.DT_Util.!TemplateDict into the
  builtins dictionary, and also provides access to a !TemplateDict
  instance through the name "_".

  - recurses into code blocks, allowing lambdas and nested function 
  definitions.

GuardedBlock security

  - 'co_names' is checked for multi-character names beginning with "_".

  - 'print' statements are replaced with calls to a function that stores
  the text in a list.  The concatenation of these strings is available
  through global variable 'printed'.  If 'printed' is not read, but 'print'
  statements are used, a warning is printed.

  - assignment statements are only allowed if the target list is a local
  or global variable name.  This prevents assignments to attributes, items,
  or slices.

  - 'del' and 'exec' statements are not allowed, and 'import' is not usable.

  - 'return', 'assert', 'try/finally', 'try/except/else', 'pass', 'raise',
  'break', 'continue', 'global', 'if/elif/else', 
  'for/else', and 'while/else' are not changed or restricted.

  - The only other statements are expression statements.  Expression
  evaluation is altered so that multiplication operations are replaced
  with calls to 'careful_mul' from '!DocumentTemplate.!VSEval'.

  - Since CodeBlock compiles a function in an empty global namespace with
  no builtins, the function is flagged restricted, and cannot access
  internal attributes such as 'im_func'.