[Python tutorial] 6. Data type - Boolean

Booleans

print(10 > 9)    # True
print(10 == 9)    # False
print(10 < 9)    # False

a = 200
b = 33

if b > a:    # False
  print("b is greater than a")
else:
  print("b is not greater than a")
# b is not greater than a

Evaluate Values and Variables: bool()

• 어떤 값을 가지고 있으면 True
• 문자열이 비었다면 False
• 0이 아닌 숫자는 True
• 비어있지 않은 list, tuple, set, dict는 True

True

print(bool("Hello"))    # True
print(bool(15))            # True

a = ""
print(bool(a))    # False

bool("abc")
bool(123)
bool(["apple", "cherry", "banana"])

False

bool(False)
bool(None)
bool(0)
bool("")
bool(())
bool([])
bool({})

class myclass():
  def __len__(self):
    return 0

myobj = myclass()
print(bool(myobj))    # False

Functions

def myFunction() :
  return True

if myFunction():
  print("YES!")
else:
  print("NO!")
# YES!

x = 200
print(isinstance(x, int)) # True