Re: yield_all needed in Python

[Nick Coghlan]

Douglas Alan wrote:
Wouldn't
   yield *(x for x in gen1(arg))
be sufficient, and would already be supported by the proposal at
hand?
It would, but, as Steven pointed out, the * in func(*args) results in 
tuple(args) being passed to the underlying function.

So I see no reason to expect "yield *iterable" to imply a for loop that yields 
the iterators contents. IMO, it's even more of a stretch than the tuple 
unpacking concept (at least that idea involves tuples!)

Whereas:
  yield x for x in iterable if condition
Maps to:
  for x in iterable:
    if condition:
      yield x
Just as:
  [x for x in iterable if condition]
Maps to:
  lc = []
  for x in iterable:
    if condition:
      lc.append(x)
And:
  (x for x in iterable if condition)
Maps to:
  def g()
    for x in iterable:
       if condition:
          yield x
And removing a couple of parentheses is at least as clear as adding an asterisk 
to the front :)

Cheers,
Nick.
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Nick Coghlan   |   [EMAIL PROTECTED]   |   Brisbane, Australia
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