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How can I use NARGIN/NARGOUT to determine the number of input/output arguments of an object method?

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I am trying to determine the number of input/output arguments of an object's method. When the name of any object method is passed to NARGIN/NARGOUT, the returned value is always -1 regardless of the number of inputs/outputs specified in the method signature.
The following syntax returns -1 for any MethodName:
nargout('MethodName')

Accepted Answer

MathWorks Support Team
MathWorks Support Team on 20 Sep 2010
The ability to call NARGIN/NARGOUT directly on object methods is not available in MATLAB. As a workaround, specify the class and method names explicitly using the following syntax:
nargout('ClassName>ClassName.MethodName')

More Answers (1)

Markus Leuthold
Markus Leuthold on 16 Apr 2015
It's almost five years later and this bug still exists. Any news from Mathworks on how to handle this situation in 2015?
Example:
Class C
classdef C < handle
methods
function r=fcn1(~)
r='run fcn1';
end
function fcn2(~)
disp('run fcn2');
end
end
end
function run
function run(f)
switch nargout(f)
case 0
feval(f);
case 1
disp(feval(f));
case -1
disp('bug')
end
What I expect from the following code
>> c=C;
>> run(@c.fcn1)
run fcn1
>> run(@c.fcn2)
run fcn2
Instead I get
>> c=C;
>> run(@c.fcn1)
bug
>> run(@c.fcn2)
bug
How do you recommend to workaround in case where you want to know nargout from a function handle AND evaluate a function handle?

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