On 11/02/2014 01:43 AM, Clayton Kirkwood wrote:
To prove that a little knowledge is a little stupid or something to that
effect:
# for key in key_list:
# print(key)
# if key not in key_list0:
# print("Error:", key, "not available, start again")
# get_new_list = True
# break
# else: get_new_list = False
Assume key_list0 = [('a', 'Ask'), ('y', 'Dividend Yield')]
The above worked when key_list was 'a y' or 'hhh'
For what definition of "worked"?
You have no comments as to what the loop is supposed to produce, nor
what its inputs are supposed to look like. Neither of the values for
key_list are lists, so what's up with that? Further, it appears you
want to compare one-letter strings to one element of a tuple.
Well, if a little cool was good why not use all of my new found knowledge of
comprehensions.
Why? There are ways to simplify it, but list comprehension isn't one of
them. I'd be looking into sets.
Something like (untested):
get_new_list = not set(key_list).issubset(set(key_list0))
So I head down the path of all sorts of variations of the following. And I
mean all sorts. Instead of [reenter, key_columns] I used a single list.
Instead of the exec('reenter = True') I used a simple reenter=True (and an
This has become total nonsense to me. There may be something you're
aiming at, but I think it's a long way from April Fool.
Perhaps you're trying for a Python obfuscation contest. But that's a C
tradition, not Python. In Python, readability is preferred.
eval and compile which I don't totally understand yet).
"exec" and "eval" ? Run for the woods.
If you like writing obscure code, then you can do it with a list
comprehension. Just wrap the comprehension in an all() or any() call.
Don't try to set external variables in an inner scope.
Something like (untested):
get_new_list = any( [ True for item in key_list if item not in
key_list0] )
This has the disadvantage that it won't stop on the first missing key,
but will try them all regardless.
In any case, you should probably make two functions, one with the
reference implementation, and one with the experiment. And your test
loop should call both of them, compare the results, and indicate when
there's a discrepancy.
--
DaveA
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