checkArgumentsBlockUsed

Checks whether an arguments block is used for input validation for the specified categories of functions among the files selected for checking. The arguments block introduced in MATLAB R2019b is very useful for input argument validation and can also be used for automatic casting. It provides a more readable and more performant alternative to functions such as inputParser, narginchk, nargin and varargin. If your code does not need to support older MATLAB releases, you might want to enable this check. Its parameters facilitate only checking publicly available functions for the presence of an arguments block. This check ignores functions that:

  • Have no input arguments.

  • Are local (subfunctions), including any functions in a script.

  • Are nested. These are not allowed to have arguments blocks anyway.

  • Have all their inputs ignored (with the ~-notation).

If a function only uses arguments blocks with the Output attribute (introduced in MATLAB R2022b), the function is reported as a violation.

Configurable parameters

  • OnlyPublicFunctions (boolean): Set this to true (default) to only check if public, visible functions and methods use arguments blocks. In addition to the list above, enabling this parameter makes the check ignore:

    • Functions in a private folder.

    • Methods with any access restriction.

    • Hidden methods.

    • Getter and setter methods.

    If the function is a method in a separate file and its class information could not be obtained (usually because of an error in the classdef file or while initializing its property values), the function will be checked and reported if there is no arguments block.

  • IgnoreSingleInputOrdinaryMethods (boolean): Set to true (default) to have this check ignore all ordinary (non-static) methods with a single input (one or more objects) that are not constructors. Adding an arguments block for these types of methods is generally not needed, and this parameter helps to prevent reporting unnecessary violations.

  • ExemptFolders (list): A list of folder-names whose files should be ignored by this check. This can be useful, for example, if you have a package folder that is not for public use. The folders of this parameter are checked for at the end of the path of a checked file. This means that specifying test as an exempt folder, makes this check ignore C:\somefolder\test\myFile.m, but it will still check C:\test\somefolder\myFile.m and C:\somefolder\foldertest\myFile.m.

    Alternatively, you can provide multiple layers for one folder. By specifying test\+internal as an exempt folder, you ignore C:\test\+internal\myFile.m, but will still check C:\otherFolder\+internal\myFile.m and C:\test\myFile.m. By default, the list is empty.

Exemption tag: %@ok<CARBU>