"Input parser" vs. new "arguments" definition

R2019b introduced the new "arguments" section for function argument checking and parsing.

I hahe written some functions using the "old" input parser class. Are there any advantages to switch to the new syntax?

Is it worth to update my functions to the new syntax? (sure, I know, "never change a running system")

regards, Stefan

[chicken vector]

Hi Stefan, this is a question of great interest.

Have you figured out an answer yet? I am implementing a library and I can't choose what to use.

Answer 1

[埃博拉酱]

The biggest advantage of the arguments block is readability, but it is far less flexible than varargin. People who are not familiar with your code can quickly understand your parameter requirements through the arguments block.

Another potential advantage may be ease of compiler optimization. Overly flexible varargin is difficult to optimize for performance.

[chicken vector]

Thank you for your answer.

I am new to using OOP in Matlab so I have been experimenting a bit with both and I would add that a limitation of using arguments over inputParser and varargin is the impossibility of using a single option input like:

options = {"parameters1", 1, "parameter2", 'foo', "parameter3", true}
myfunction(requiredInput, options)

When you use arguments you are obligated to write instead:

myfunction(requiredInput, "parameters1", 1, "parameter2", 'foo', "parameter3", true)

This can be a little boring when you have to pass options between sub/superclasses.

Nevertheless, I could be wrong about this due to my inexperience.

[埃博拉酱]

From your description, I don't quite understand what you're trying to do.

[Simon]

I have the same question. Both inputParser and arguments are unfamiliar to me.

[Stephen23]

@chicken vector: you can always use a comma-separated list, which works on every MATLAB version**:

options = {"parameters1", 1, "parameter2", 'foo', "parameter3", true}
myfunction(requiredInput, options{:})

https://www.mathworks.com/help/matlab/matlab_prog/comma-separated-lists.html

https://www.mathworks.com/matlabcentral/answers/1656435-tutorial-comma-separated-lists-and-how-to-use-them

** with cell arrays. AFAIK comma-separated lists were introduced at the same time.