On 4/25/2011 1:21 PM, Rob Cliffe wrote:
>>> type (3.)
<type 'float'>
>>> 3..__class__
<type 'float'>
>>> type(3)
<type 'int'>
>>> 3.__class__
File "<stdin>", line 1
3.__class__
^
SyntaxError: invalid syntax
Superficially the last example ought to be legal syntax (and return
<type 'int'>).
You are a more sophisticated parser than Python, which is limited to
LL(1) parsing. (No that is not in the manual, but it is a known design
consraint.)
Is it an oversight which could be fixed in a straightforward way, or are
there reasons why it can't?
This sort of question as to why Python is the way it is really belongs
on python-list.
3.x is parsed as (3.)x (float 3. followed by x) which is invalid syntax
unless 'x' is a digit(s). You automatically back up and reparse as 3(.x)
3 .0 is a syntax error.
3 .__class__ is int.
--
Terry Jan Reedy
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