如何在Python 3中停止exec命令内部的执行?

在这里,就这样做:

class ExecInterrupt(Exception):
    pass

def Exec(source, globals=None, locals=None):
    try:
        exec(source, globals, locals)
    except ExecInterrupt:
        pass

Exec("""
print("foo")

if True: 
    raise ExecInterrupt

print("bar")
""")
print('This should still be executed')

这将起作用,返回仅在定义的函数中起作用:

code = """
print("foo")

if not True:
    print("bar")
"""
exec(code)
print('This should still be executed')

code = """
def func():
    print("foo")

    if True: 
        return

    print("bar")

func()    
"""
exec(code)
print('This should still be executed')

没有内置机制允许您中止 exec 打电话来。我们最接近的是 sys.exit() ,但这会退出整个程序,而不仅仅是 执行官 . 幸运的是,这可以通过少量的异常处理样板来解决:

my_code = """
import sys

print("foo")

if True: 
    sys.exit()

print("bar")
"""

try:
    exec(my_code)
except SystemExit:
    pass
print('This is still executed')

# output:
# foo
# This is still executed

def breakable_exec(code):
    exec('for _ in [0]:' + '\n'.join("    " + line for line in code.splitlines()))

code = """
print("foo")

if True: 
    break

print("bar")
"""

breakable_exec(code)
# => foo