Extend scope of variables to other local functions

I have a function that uses a few helper functions. I'd like these helper functions to have access to variables without:

• passing variables
• making nested functions
• making globals

E.g. when I call a local function from another function in the same m-file, the body of the called function is evaluated in the scope/namespace of the caller. As far as I know `evalin()` only works with single expressions.

[Stephen23]

Passing arguments or using nested functions would be the simplest, most reliable, and robust way of achieving this. These are the methods that the MATLAB documentation recommends, and that are recommended practice in many other languages and coding standards. Any hack code that you could invent using evalin, global or the like is going to be much slower and buggier.

Why do you want to avoid using the two best solutions that you have available to you?

http://www.mathworks.com/help/matlab/matlab_prog/share-data-between-workspaces.html

[Adam]

Passing variables is the bread and butter of programming and designing good code really. On occasions where I find I am having to pass a ridiculous number of variables it is a clear sign my design is bad, though sometimes I do it still because I don't have time for better design!

I have occasionally made use of nested functions where it has seemed neat, though I don't like the fact that they lock the workspace so that when debugging you cannot create new variables on command line which is something I do regularly.

[Jurgen]

C++ uses namespaces that lets functions cover specific scopes. It just makes sense to give a programmer finer control over the variable scope, as opposed to just global or local. Even just global within a single m-file would be useful, as my m-files are sets of related functions, almost like classes.

[Adam]

I do certainly miss namespaces from C++

[Guillaume]

In C++, unless your variables are extern static (i.e. matlab's global) you won't be able to share variables between functions in different files even at the namespace scope.

Answer 1

[Guillaume]

my m-files are sets of related functions, almost like classes

Then use classes, you can have your shared variables as private properties of the class, and your functions as methods of the class.