Method that takes a method as a parameter with an optional parameter
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1
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I have two methods from a library that work in the same manner. The difference is that one takes an additional, optional parameter. For example:
def method1(a, b, c):
...
def method2(a, b, c, d=None):
...
I have to perform the same task on the results of these methods, so I have a method that combines them that looks like this:
def wrapper(method, a, b, c, d=None):
...
if d:
results = method(a, b, c, d=d)
else:
results = method(a, b, c)
...
This works, but as I add more methods that have different optional arguments it becomes cumbersome. Is there a way a better way to handle these parameters?
python methods optional-parameters
asked Nov 9 at 17:47
billypilgrim
456
add a comment |
up vote
1
down vote
favorite
I have two methods from a library that work in the same manner. The difference is that one takes an additional, optional parameter. For example:
def method1(a, b, c):
...
def method2(a, b, c, d=None):
...
I have to perform the same task on the results of these methods, so I have a method that combines them that looks like this:
def wrapper(method, a, b, c, d=None):
...
if d:
results = method(a, b, c, d=d)
else:
results = method(a, b, c)
...
This works, but as I add more methods that have different optional arguments it becomes cumbersome. Is there a way a better way to handle these parameters?
python methods optional-parameters
asked Nov 9 at 17:47
billypilgrim
456
2
Look at the*operator for function arguments; I suspect you can solve your problem from there with a simple list of arguments, such asresults = method(*arg_list)
– Prune
Nov 9 at 17:51
try**kwargsfor the parameterd.
– Naveen
Nov 9 at 17:52
Are these methods or functions? But I agree, probably best if you modify the methods/functions to handle the args/kwargs conditionally.
– Idlehands
Nov 9 at 18:33
In my case, method 1 and 2 are actually methods and the wrapper is a function, but I was trying to generalize for this example. I didn't realize*argsas a whole could be passed through.
– billypilgrim
Nov 10 at 17:23
add a comment |
up vote
1
down vote
favorite
up vote
1
down vote
favorite
I have two methods from a library that work in the same manner. The difference is that one takes an additional, optional parameter. For example:
def method1(a, b, c):
...
def method2(a, b, c, d=None):
...
I have to perform the same task on the results of these methods, so I have a method that combines them that looks like this:
def wrapper(method, a, b, c, d=None):
...
if d:
results = method(a, b, c, d=d)
else:
results = method(a, b, c)
...
This works, but as I add more methods that have different optional arguments it becomes cumbersome. Is there a way a better way to handle these parameters?
python methods optional-parameters
asked Nov 9 at 17:47
billypilgrim
456
I have two methods from a library that work in the same manner. The difference is that one takes an additional, optional parameter. For example:
def method1(a, b, c):
...
def method2(a, b, c, d=None):
...
I have to perform the same task on the results of these methods, so I have a method that combines them that looks like this:
def wrapper(method, a, b, c, d=None):
...
if d:
results = method(a, b, c, d=d)
else:
results = method(a, b, c)
...
This works, but as I add more methods that have different optional arguments it becomes cumbersome. Is there a way a better way to handle these parameters?
python methods optional-parameters
python methods optional-parameters
asked Nov 9 at 17:47
billypilgrim
456
asked Nov 9 at 17:47
billypilgrim
456
asked Nov 9 at 17:47
billypilgrim
456
asked Nov 9 at 17:47
billypilgrim
456
asked Nov 9 at 17:47
billypilgrim
456
456
2
Look at the*operator for function arguments; I suspect you can solve your problem from there with a simple list of arguments, such asresults = method(*arg_list)
– Prune
Nov 9 at 17:51
try**kwargsfor the parameterd.
– Naveen
Nov 9 at 17:52
Are these methods or functions? But I agree, probably best if you modify the methods/functions to handle the args/kwargs conditionally.
– Idlehands
Nov 9 at 18:33
In my case, method 1 and 2 are actually methods and the wrapper is a function, but I was trying to generalize for this example. I didn't realize*argsas a whole could be passed through.
– billypilgrim
Nov 10 at 17:23
add a comment |
2
Look at the*operator for function arguments; I suspect you can solve your problem from there with a simple list of arguments, such asresults = method(*arg_list)
– Prune
Nov 9 at 17:51
try**kwargsfor the parameterd.
– Naveen
Nov 9 at 17:52
Are these methods or functions? But I agree, probably best if you modify the methods/functions to handle the args/kwargs conditionally.
– Idlehands
Nov 9 at 18:33
In my case, method 1 and 2 are actually methods and the wrapper is a function, but I was trying to generalize for this example. I didn't realize*argsas a whole could be passed through.
– billypilgrim
Nov 10 at 17:23
2
2
Look at the
* operator for function arguments; I suspect you can solve your problem from there with a simple list of arguments, such as results = method(*arg_list)– Prune
Nov 9 at 17:51
Look at the
* operator for function arguments; I suspect you can solve your problem from there with a simple list of arguments, such as results = method(*arg_list)– Prune
Nov 9 at 17:51
try
**kwargs for the parameter d.– Naveen
Nov 9 at 17:52
try
**kwargs for the parameter d.– Naveen
Nov 9 at 17:52
Are these methods or functions? But I agree, probably best if you modify the methods/functions to handle the args/kwargs conditionally.
– Idlehands
Nov 9 at 18:33
Are these methods or functions? But I agree, probably best if you modify the methods/functions to handle the args/kwargs conditionally.
– Idlehands
Nov 9 at 18:33
In my case, method 1 and 2 are actually methods and the wrapper is a function, but I was trying to generalize for this example. I didn't realize
*args as a whole could be passed through.– billypilgrim
Nov 10 at 17:23
In my case, method 1 and 2 are actually methods and the wrapper is a function, but I was trying to generalize for this example. I didn't realize
*args as a whole could be passed through.– billypilgrim
Nov 10 at 17:23
add a comment |
2 Answers
2
active
oldest
votes
up vote
1
down vote
Here is some code that might accomplish what you're looking for.
You can pass a collection of methods into wrapper and that function will return the value of any method that has key word arguments mapped to kwargs.
def method1(a, b, c):
return a, b, c
def method2(a, b, c, d=None):
return a, b, c, d
methods = (
method1,
method2,
) # Collection of methods to run.
def wrapper(kwargs, methods=methods):
"""Loop over methods with kwargs."""
for method in methods:
try: # Call method with **kwargs
return method(**kwargs) # Return value if keys in kwargs fit signature of method.
except TypeError as err: # Handle error if keyword args don't match.
print(f'err "{err}" for method "{method}')
kwargs_collection = (dict(zip(args, (f'value for arg: "{arg}"' for arg in args)))
for args in ('abcd', 'abc', ))
for test_kwargs in kwargs_collection:
print(wrapper(test_kwargs))
OUTPUT:
err "method1() got an unexpected keyword argument 'd'" for method "function method1 at 0x7f900c2b7d90"
('value for arg: "a"', 'value for arg: "b"', 'value for arg: "c"', 'value for arg: "d"')
('value for arg: "a"', 'value for arg: "b"', 'value for arg: "c"')
answered Nov 9 at 18:55
DMfll
92311828
add a comment |
up vote
0
down vote
For the wrapper function, I decided to just do something like the following as suggested in the comments:
def wrapper(method, *args):
...
results = method(*args)
...
Error handling should be incorporated to make sure the proper arguments are being passed as well, as suggested in another answer.
answered Nov 10 at 17:18
billypilgrim
456
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
1
down vote
Here is some code that might accomplish what you're looking for.
You can pass a collection of methods into wrapper and that function will return the value of any method that has key word arguments mapped to kwargs.
def method1(a, b, c):
return a, b, c
def method2(a, b, c, d=None):
return a, b, c, d
methods = (
method1,
method2,
) # Collection of methods to run.
def wrapper(kwargs, methods=methods):
"""Loop over methods with kwargs."""
for method in methods:
try: # Call method with **kwargs
return method(**kwargs) # Return value if keys in kwargs fit signature of method.
except TypeError as err: # Handle error if keyword args don't match.
print(f'err "{err}" for method "{method}')
kwargs_collection = (dict(zip(args, (f'value for arg: "{arg}"' for arg in args)))
for args in ('abcd', 'abc', ))
for test_kwargs in kwargs_collection:
print(wrapper(test_kwargs))
OUTPUT:
err "method1() got an unexpected keyword argument 'd'" for method "function method1 at 0x7f900c2b7d90"
('value for arg: "a"', 'value for arg: "b"', 'value for arg: "c"', 'value for arg: "d"')
('value for arg: "a"', 'value for arg: "b"', 'value for arg: "c"')
answered Nov 9 at 18:55
DMfll
92311828
add a comment |
up vote
1
down vote
Here is some code that might accomplish what you're looking for.
You can pass a collection of methods into wrapper and that function will return the value of any method that has key word arguments mapped to kwargs.
def method1(a, b, c):
return a, b, c
def method2(a, b, c, d=None):
return a, b, c, d
methods = (
method1,
method2,
) # Collection of methods to run.
def wrapper(kwargs, methods=methods):
"""Loop over methods with kwargs."""
for method in methods:
try: # Call method with **kwargs
return method(**kwargs) # Return value if keys in kwargs fit signature of method.
except TypeError as err: # Handle error if keyword args don't match.
print(f'err "{err}" for method "{method}')
kwargs_collection = (dict(zip(args, (f'value for arg: "{arg}"' for arg in args)))
for args in ('abcd', 'abc', ))
for test_kwargs in kwargs_collection:
print(wrapper(test_kwargs))
OUTPUT:
err "method1() got an unexpected keyword argument 'd'" for method "function method1 at 0x7f900c2b7d90"
('value for arg: "a"', 'value for arg: "b"', 'value for arg: "c"', 'value for arg: "d"')
('value for arg: "a"', 'value for arg: "b"', 'value for arg: "c"')
answered Nov 9 at 18:55
DMfll
92311828
add a comment |
up vote
1
down vote
up vote
1
down vote
Here is some code that might accomplish what you're looking for.
You can pass a collection of methods into wrapper and that function will return the value of any method that has key word arguments mapped to kwargs.
def method1(a, b, c):
return a, b, c
def method2(a, b, c, d=None):
return a, b, c, d
methods = (
method1,
method2,
) # Collection of methods to run.
def wrapper(kwargs, methods=methods):
"""Loop over methods with kwargs."""
for method in methods:
try: # Call method with **kwargs
return method(**kwargs) # Return value if keys in kwargs fit signature of method.
except TypeError as err: # Handle error if keyword args don't match.
print(f'err "{err}" for method "{method}')
kwargs_collection = (dict(zip(args, (f'value for arg: "{arg}"' for arg in args)))
for args in ('abcd', 'abc', ))
for test_kwargs in kwargs_collection:
print(wrapper(test_kwargs))
OUTPUT:
err "method1() got an unexpected keyword argument 'd'" for method "function method1 at 0x7f900c2b7d90"
('value for arg: "a"', 'value for arg: "b"', 'value for arg: "c"', 'value for arg: "d"')
('value for arg: "a"', 'value for arg: "b"', 'value for arg: "c"')
answered Nov 9 at 18:55
DMfll
92311828
Here is some code that might accomplish what you're looking for.
You can pass a collection of methods into wrapper and that function will return the value of any method that has key word arguments mapped to kwargs.
def method1(a, b, c):
return a, b, c
def method2(a, b, c, d=None):
return a, b, c, d
methods = (
method1,
method2,
) # Collection of methods to run.
def wrapper(kwargs, methods=methods):
"""Loop over methods with kwargs."""
for method in methods:
try: # Call method with **kwargs
return method(**kwargs) # Return value if keys in kwargs fit signature of method.
except TypeError as err: # Handle error if keyword args don't match.
print(f'err "{err}" for method "{method}')
kwargs_collection = (dict(zip(args, (f'value for arg: "{arg}"' for arg in args)))
for args in ('abcd', 'abc', ))
for test_kwargs in kwargs_collection:
print(wrapper(test_kwargs))
OUTPUT:
err "method1() got an unexpected keyword argument 'd'" for method "function method1 at 0x7f900c2b7d90"
('value for arg: "a"', 'value for arg: "b"', 'value for arg: "c"', 'value for arg: "d"')
('value for arg: "a"', 'value for arg: "b"', 'value for arg: "c"')
answered Nov 9 at 18:55
DMfll
92311828
edited Nov 10 at 16:58
answered Nov 9 at 18:55
DMfll
92311828
answered Nov 9 at 18:55
DMfll
92311828
answered Nov 9 at 18:55
DMfll
92311828
92311828
add a comment |
add a comment |
up vote
0
down vote
For the wrapper function, I decided to just do something like the following as suggested in the comments:
def wrapper(method, *args):
...
results = method(*args)
...
Error handling should be incorporated to make sure the proper arguments are being passed as well, as suggested in another answer.
answered Nov 10 at 17:18
billypilgrim
456
add a comment |
up vote
0
down vote
For the wrapper function, I decided to just do something like the following as suggested in the comments:
def wrapper(method, *args):
...
results = method(*args)
...
Error handling should be incorporated to make sure the proper arguments are being passed as well, as suggested in another answer.
answered Nov 10 at 17:18
billypilgrim
456
add a comment |
up vote
0
down vote
up vote
0
down vote
For the wrapper function, I decided to just do something like the following as suggested in the comments:
def wrapper(method, *args):
...
results = method(*args)
...
Error handling should be incorporated to make sure the proper arguments are being passed as well, as suggested in another answer.
answered Nov 10 at 17:18
billypilgrim
456
For the wrapper function, I decided to just do something like the following as suggested in the comments:
def wrapper(method, *args):
...
results = method(*args)
...
Error handling should be incorporated to make sure the proper arguments are being passed as well, as suggested in another answer.
answered Nov 10 at 17:18
billypilgrim
456
answered Nov 10 at 17:18
billypilgrim
456
answered Nov 10 at 17:18
billypilgrim
456
answered Nov 10 at 17:18
billypilgrim
456
456
add a comment |
add a comment |
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2
Look at the
*operator for function arguments; I suspect you can solve your problem from there with a simple list of arguments, such asresults = method(*arg_list)– Prune
Nov 9 at 17:51
try
**kwargsfor the parameterd.– Naveen
Nov 9 at 17:52
Are these methods or functions? But I agree, probably best if you modify the methods/functions to handle the args/kwargs conditionally.
– Idlehands
Nov 9 at 18:33
In my case, method 1 and 2 are actually methods and the wrapper is a function, but I was trying to generalize for this example. I didn't realize
*argsas a whole could be passed through.– billypilgrim
Nov 10 at 17:23