这个关于perl中无限循环的问题很感兴趣:while(1)vs.for(;;)有速度差吗?,我决定在python中运行类似的比较.我期望编译器会为while(True): pass和生成相同的字节代码while(1): pass,但实际上并非python2.7中的情况.
以下脚本:
import dis
def while_one():
while 1:
pass
def while_true():
while True:
pass
print("while 1")
print("----------------------------")
dis.dis(while_one)
print("while True")
print("----------------------------")
dis.dis(while_true)
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产生以下结果:
while 1
----------------------------
4 0 SETUP_LOOP 3 (to 6)
5 >> 3 JUMP_ABSOLUTE 3
>> 6 LOAD_CONST 0 (None)
9 RETURN_VALUE
while True
----------------------------
8 0 SETUP_LOOP 12 (to 15)
>> 3 LOAD_GLOBAL 0 (True)
6 JUMP_IF_FALSE 4 (to 13)
9 POP_TOP
9 10 JUMP_ABSOLUTE 3
>> 13 POP_TOP …Run Code Online (Sandbox Code Playgroud) python ×1