Catch exception and continue try block in Python
PythonExceptionPython Problem Overview
Can I return to executing the try
block after exception occurs?
For example:
try:
do_smth1()
except:
pass
try:
do_smth2()
except:
pass
vs.
try:
do_smth1()
do_smth2()
except:
??? # magic word to proceed to do_smth2() if there was exception in do_smth1
Python Solutions
Solution 1 - Python
No, you cannot do that. That's just the way Python has its syntax. Once you exit a try-block because of an exception, there is no way back in.
What about a for-loop though?
funcs = do_smth1, do_smth2
for func in funcs:
try:
func()
except Exception:
pass # or you could use 'continue'
Note however that it is considered a bad practice to have a bare except
. You should catch for a specific exception instead. I captured for Exception
because that's as good as I can do without knowing what exceptions the methods might throw.
Solution 2 - Python
While the other answers and the accepted one are correct and should be followed in real code, just for completeness and humor, you can try the fuckitpy
( https://github.com/ajalt/fuckitpy ) module.
Your code can be changed to the following:
@fuckitpy
def myfunc():
do_smth1()
do_smth2()
Then calling myfunc()
would call do_smth2()
even if there is an exception in do_smth1())
Note: Please do not try it in any real code, it is blasphemy
Solution 3 - Python
You can achieve what you want, but with a different syntax. You can use a "finally" block after the try/except. Doing this way, python will execute the block of code regardless the exception was thrown, or not.
Like this:
try:
do_smth1()
except:
pass
finally:
do_smth2()
But, if you want to execute do_smth2() only if the exception was not thrown, use a "else" block:
try:
do_smth1()
except:
pass
else:
do_smth2()
You can mix them too, in a try/except/else/finally clause. Have fun!
Solution 4 - Python
You could iterate through your methods...
for m in [do_smth1, do_smth2]:
try:
m()
except:
pass
Solution 5 - Python
one way you could handle this is with a generator. Instead of calling the function, yield it; then whatever is consuming the generator can send the result of calling it back into the generator, or a sentinel if the generator failed: The trampoline that accomplishes the above might look like so:
def consume_exceptions(gen):
action = next(gen)
while True:
try:
result = action()
except Exception:
# if the action fails, send a sentinel
result = None
try:
action = gen.send(result)
except StopIteration:
# if the generator is all used up, result is the return value.
return result
a generator that would be compatible with this would look like this:
def do_smth1():
1 / 0
def do_smth2():
print "YAY"
def do_many_things():
a = yield do_smth1
b = yield do_smth2
yield "Done"
>>> consume_exceptions(do_many_things())
YAY
Note that do_many_things()
does not call do_smth*
, it just yields them, and consume_exceptions
calls them on its behalf
Solution 6 - Python
'continue' is allowed within an 'except' or 'finally' only if the try block is in a loop. 'continue' will cause the next iteration of the loop to start.
So you can try put your two or more functions in a list and use loop to call your function.
Like this:
funcs = [f,g]
for func in funcs:
try: func()
except: continue
Solution 7 - Python
I don't think you want to do this. The correct way to use a try
statement in general is as precisely as possible. I think it would be better to do:
try:
do_smth1()
except Stmnh1Exception:
# handle Stmnh1Exception
try:
do_smth2()
except Stmnh2Exception:
# handle Stmnh2Exception
Solution 8 - Python
Depending on where and how often you need to do this, you could also write a function that does it for you:
def live_dangerously(fn, *args, **kw):
try:
return fn(*args, **kw)
except Exception:
pass
live_dangerously(do_smth1)
live_dangerously(do_smth2)
But as other answers have noted, having a null except
is generally a sign something else is wrong with your code.
Solution 9 - Python
special_func to avoid try-except repetition:
def special_func(test_case_dict):
final_dict = {}
exception_dict = {}
def try_except_avoider(test_case_dict):
try:
for k,v in test_case_dict.items():
final_dict[k]=eval(v) #If no exception evaluate the function and add it to final_dict
except Exception as e:
exception_dict[k]=e #extract exception
test_case_dict.pop(k)
try_except_avoider(test_case_dict) #recursive function to handle remaining functions
finally: #cleanup
final_dict.update(exception_dict)
return final_dict #combine exception dict and final dict
return try_except_avoider(test_case_dict)
Run code:
def add(a,b):
return (a+b)
def sub(a,b):
return (a-b)
def mul(a,b):
return (a*b)
case = {"AddFunc":"add(8,8)","SubFunc":"sub(p,5)","MulFunc":"mul(9,6)"}
solution = special_func(case)
Output looks like:
{'AddFunc': 16, 'MulFunc': 54, 'SubFunc': NameError("name 'p' is not defined")}
To convert to variables:
locals().update(solution)
Variables would look like:
AddFunc = 16, MulFunc = 54, SubFunc = NameError("name 'p' is not defined")
Solution 10 - Python
This can be done with exec()
in a custom function, a list of strings, and a for
loop.
The function with exec()
:
def try_it(string):
try:
exec(string)
print(f'Done: {string}')
except:
print(f'Error. Could not do: {string}')
More on exec():
exec(object)
This function supports dynamic execution of Python code. object must be either a string or a code object.
Example list of strings and for
loop:
do_smth_list = ['do_smth1()', 'do_smth2()', 'do_smth3()']
for smth in do_smth_list:
try_it(smth)
Solution 11 - Python
I might be wrong and this definitely isn't the cleanest way of doing it, but you can put it in a while loop with a variable set to true, and when it runs the function successfully it sets the variable to false, whereas if it fails it keeps the variable set to true.
x = True
while x == True:
try:
do_smth1()
x = False
except:
x = True
pass
This way what happens is that the while loop will keep on looping the try except section again and again until it works, in which x is set to false and the loop stops
I'm sorry if I haven't used the correct technical terms or coded something wrong I'm still pretty new to python