[Chicago] newbie says HI; needs help

[Andrew Dudzik]

Hello!  I'm also new, to both Python and this list, but I think I know this
one, so it's a good chance for me to post.

The second block of code doesn't work either--it always sets stock = 2.  I
believe that the problem is that the code you've really written is:

if (texture == "flaky") or "caked":
...

If either expression evaluates to True, the first block will be called.
Problem is, bool("caked") evaluates to True, as bool(s) is False if s == ""
and True otherwise, when s is a string.  The reason for this is it allows
for really brief code like, I dunno:

a = "Hello."
while a:
    a = a[:-1]

This removes a character from the end of a until a is empty.

This code would work:

if texture == "flaky" or texture == "caked":
    stock = 1
else:
    stock = 2


The problem with learning Python from a Pascal book is that you're going to
miss all of the syntactical shortcuts that makes Python powerful.  For
instance, you could use the line 'if texture in ["flaky","caked"]'.  There's
definitely a good one-liner for this, (the veterans should chime in here)
but the best I could come up with was this one: (it's a hack)

stock = 2 - (texture in ["flaky","caked"])


if texture == "flaky" or "caked":
>     stock = 1
>  else:
>     stock = 2
>
> This never worked.  Cigars with "varied, fluffy, granular, " textures
> always ended up as stock 1.  So did the "flaky and caked".
>
> -----------------------------------------------------------------------------
>
> When I changed the line to:
>
> if texture != "flaky" or "caked":
>     stock = 2
> else:
>     stock = 1
> the program works great.   I have no idea why.  Can anyone help me.
>
>
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