How this expression 'a' <= c <= 'z' is evaluated in Python

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I would like to know the evaluation order of this expression in Python:

if 'a' <= c <= 'z': # c é uma variável de tipo `chr`
    print("Ronal... D'oh!")
python characteristic-language

1 answer

5


She’s rated left to right, like:

'a' <= c and c <= 'z'

Moreover, if c was an expression with side effects, like

a() <= c() <= z()

The call to c() only occur once, still in left-to-right order, i.e. after a() and before z(). Source.

Another example:

>>> def a():
...   print('a')
...   return 'a'
...
>>> def z():
...   print('z')
...   return 'z'
...
>>> if a() <= 'c' <= z():
...   print('ok')
...
a
z
ok
>>> if a() <= 'A' <= z():
...   print('ok')
...
a
>>>

Note that as in the latter case the first comparison gave False, the second was not performed (short circuit).

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