diff options
Diffstat (limited to 'python.html.markdown')
-rw-r--r-- | python.html.markdown | 29 |
1 files changed, 21 insertions, 8 deletions
diff --git a/python.html.markdown b/python.html.markdown index 0bd16a80..0b115c4e 100644 --- a/python.html.markdown +++ b/python.html.markdown @@ -85,12 +85,24 @@ False - 5 # => -5 2 == True # => False -5 != False # => True -# Using boolean logical operators on ints casts them to booleans for evaluation, but their non-cast value is returned -# Don't mix up with bool(ints) and bitwise and/or (&,|) +# None, 0, and empty strings/lists/dicts/tuples/sets all evaluate to False. +# All other values are True bool(0) # => False +bool("") # => False +bool([]) # => False +bool({}) # => False +bool(()) # => False +bool(set()) # => False bool(4) # => True bool(-6) # => True + +# Using boolean logical operators on ints casts them to booleans for evaluation, but their non-cast value is returned +# Don't mix up with bool(ints) and bitwise and/or (&,|) +bool(0) # => False +bool(2) # => True 0 and 2 # => 0 +bool(-5) # => True +bool(2) # => True -5 or 0 # => -5 # Equality is == @@ -153,13 +165,14 @@ None # => None "etc" is None # => False None is None # => True -# None, 0, and empty strings/lists/dicts/tuples all evaluate to False. +# None, 0, and empty strings/lists/dicts/tuples/sets all evaluate to False. # All other values are True -bool(0) # => False -bool("") # => False -bool([]) # => False -bool({}) # => False -bool(()) # => False +bool(0) # => False +bool("") # => False +bool([]) # => False +bool({}) # => False +bool(()) # => False +bool(set()) # => False #################################################### ## 2. Variables and Collections |