Re: How to detect what type a variable is?

I want to know what type is a variable.

You should try to treat it as a list, catch the exceptions
raise when it is a string (problably ValueError, TypeError ou
Attribute error, depends on what are you doing), and then
treat it as a string. This is the BAFP (better ask for
forgiveness than permission) style


One might prefer to check for string-ness, as strings can duck-type somewhat like lists:

my_list = ['my', 'brain', 'hurts']
my_string = 'Are you the brain specialist?'

for test in [my_list, my_string]:
try:
for thing in test:
process_list_item(thing)
except Exception: #whatever flavor you want
process_string(thing) # not called because
#strings are iterable


This gives the potentially-surprising result of iterating over my_string and calling process_list_item() with each character in the string, rather than raising some exception and calling process_string(). Python does the right thing, but it can be confusing when the duck-typing syntax is identical for the two, despite a desire to treat them differently...perhaps a tree-like list of lists and strings such as HTML/XML structure.

-tkc



.

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