# ----- ----- List Builder
1 a = [x*2 for x in range(10)]
2 print(a,type(a)) #[0, 2, 4, 6, 8, 10, 12, 14, 16, 18] <class 'list'>
3
4 def f(n):
5 return n**3
6
7 a = [f(x) for x in range(10)]
8 print(a,type(a)) #[0, 1, 8, 27, 64, 125, 216, 343, 512, 729] <class 'list'>
# ----- simple assignment mode
1 t = (12,45)
2 a,b = t
3 print(a)#12
4 print(b)#45
# ---- Generator (generator is iterable) -----
. 1 S = (X * 2 for X in Range (10 ))
2 for I in S:
. 3 Print (I, End = " " ) # 0 2. 4. 6. 8 10 12 is 14 16 18 is
. 4
. 5 # iterables: internal there iter method
. 6 A = (1, 2,3,5 )
. 7 . A the __iter__ ()
. 8 B = [2,3,4,5 ]
. 9 . B the __iter__ ()
10 C = { " A " : " D " , " G ":"r"}
11 c.__iter__()
12 e = set(a)
13 print(e,type(e))
14 e.__iter__()
# ----- yield keywords to generate Fibonacci number
1 def fib(max):
2 n,before,after = 0,0,1
3 while n < max:
4 yield after
5 before,after = after,before+after
6 n += 1
7
8 g = fib(6)
9 for i in g:
10 print(i)
# ----- yield using
1 def bar():
2 print("ok1")
3 str1 = yield 1
4 print(str1)
5
6 print("ok2")
7 str2 = yield 2
8 print(str2)
9 b = bar()
10 next(b)
11 ret = b.send("ee")
12 print(ret)
# ----- concurrent operation may also be implemented to achieve the effect in case of single-threaded through yield
. 1 Import Time
2
. 3 DEF Tourist (name):
. 4 Print ( " % s Start bun " % name)
. 5 the while True:
. 6 Baozi = the yield # generator function (Generator)
. 7 Print ( " % s% s of eating a " % (name, Baozi))
. 8
. 9 DEF Cook (name):
10 C1 = Tourist ( " A " )
. 11 C2 = Tourist ( " B " )
12 is . C1 __next__ ()
13 is . C2 __next__ ()
14 Print ( " % S started buns " % name)
15 for I in Range (1,10 ):
16 the time.sleep (0.2 )
. 17 c1.send (I)
18 is c2.send (I)
. 19 Cook ( " Dream " )
View Code
----- # ----- iterator
1, there are iter method
2, the next method
1 a = ["dream","rise","happy"]
2 d = iter(a) #<list_iterator object at 0x000001E01BFADA90>
3 print(d)
4 print(a.__iter__())#<list_iterator object at 0x00000258F8392668>