[Python-Dev] Tuple pack/unpack and the definition of AST Assign nodes

[Thomas Lee]

Nick Coghlan wrote:
>
> I haven't looked at that code recently, but I believe the ADSL 
> sequence in the assignment node is for statements where there are 
> actually multiple assignment targets, such as:
>
> >>> p = x, y = 1, 2
> >>> p, x, y
> ((1, 2), 1, 2)
>
> Cheers,
> Nick.
>
Ah I see. A quick test verifies exactly this:

    >>> import _ast
    >>> ast = compile("p = x, y = 1, 2", "<string>", "exec", 
_ast.PyCF_ONLY_AST)
    >>> ast.body[0]
    <_ast.Assign object at 0xb7d0122c>
    >>> ast.body[0].targets
    [<_ast.Name object at 0xb7d0124c>, <_ast.Tuple object at 0xb7d0128c>]
    >>> ast.body[0].value
    <_ast.Tuple object at 0xb7d0132c>
    >>>

I thought this would have been implemented as nested Assign nodes, but 
I'm obviously wrong. :) Thanks for the clarification.

Cheers,
T