odd behaviour when making lists of lambda forms

[jhidding]

BPO	1326195
Nosy	@rhettinger

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = None
closed_at = <Date 2005-10-14.14:41:44.000>
created_at = <Date 2005-10-13.20:56:32.000>
labels = ['interpreter-core', 'invalid']
title = 'odd behaviour when making lists of lambda forms'
updated_at = <Date 2005-10-14.14:41:44.000>
user = 'https://bugs.python.org/jhidding'

bugs.python.org fields:

activity = <Date 2005-10-14.14:41:44.000>
actor = 'rhettinger'
assignee = 'none'
closed = True
closed_date = None
closer = None
components = ['Interpreter Core']
creation = <Date 2005-10-13.20:56:32.000>
creator = 'jhidding'
dependencies = []
files = []
hgrepos = []
issue_num = 1326195
keywords = []
message_count = 2.0
messages = ['26589', '26590']
nosy_count = 2.0
nosy_names = ['rhettinger', 'jhidding']
pr_nums = []
priority = 'normal'
resolution = 'not a bug'
stage = None
status = 'closed'
superseder = None
type = None
url = 'https://bugs.python.org/issue1326195'
versions = ['Python 2.3']

[jhidding]

Hi,

I don't know if this is really a bug, but it is odd. I
tried to make a list of lambda forms like in the
following example, but the functions thus created don't
really do what I expect.

**************
Python 2.3.5 (#2, Jun 19 2005, 13:28:00) 
[GCC 3.3.6 (Debian 1:3.3.6-6)] on linux2
Type "help", "copyright", "credits" or "license" for
more information.
>>> p = [lambda t: t**n for n in range(6)]
>>> p[0](2)
32
>>> p
[<function <lambda> at 0xb7cece64>, <function <lambda>
at 0xb7cf10d4>, <function <lambda> at 0xb7cf1b1c>,
<function <lambda> at 0xb7cf1b54>, <function <lambda>
at 0xb7cf1b8c>, <function <lambda> at 0xb7cf1bc4>]
>>> p[1](2)
32
>>> p[1](5)
3125
****************
While:
****************
>>> q = [lambda t: 1, lambda t: t, lambda t: t**2,
lambda t: t**3, lambda t: t**4]
>>> q[0](4)
1
>>> q[1](4)
4
>>> q[2](4)
16
***************

I tried creating the list using a for loop, but it
shows the same weird behaviour. Also any attempt to put
the lambda form in an object didn't give a cure.

say: 
Wrap(lambda x: x**2)
creates a callable object storing the lambda form as a
data member.
****
>>> j = [Wrap(lambda t: t**n) for n in range(5)]
>>> j[0](1)
1
>>> j[0](3)
81
>>> j[0](5)
625
****

Both Python 2.3 and 2.4 show this behaviour. Am I
completely overlooking something, or...?

kind regards,

Johan Hidding
Groningen, the Netherlands

[rhettinger]

Logged In: YES
user_id=80475

Try this:
p = [lambda t, n=n: t**n for n in range(6)]