Re: [Tutor] Is there a test for hashability?

[Emile van Sebille]

On 9/1/2011 11:30 AM Chris Fuller said...

On Thursday 01 September 2011, Richard D. Moores wrote:

Thanks, James, from your ideas I've come up with this function as a
general test for hashibility of any object:

def is_hashable(object):
     try:
         if hash(object):
             return True
     except TypeError:
         return False

But is it?  It returns True for ints, floats, sets, tuples, strings,
functions; and False for lists

Dick
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You shouldn't be checking the truth value of the hash.  If it's zero, this
function will fall through and return None!

def is_hashable(object):
    try:
         hash(object):
             return True
     except TypeError:
         return False

Is what you want.

You should, of course, express it as valid python code though. :)

def is_hashable(object):
    try:
         hash(object)
         return True
     except TypeError:
         return False


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