Display error message and execute catch

Hello, all. I've got a fairly simple question, and I can't seem to find the answer. If I have a try/catch block, I would like the error to be displayed in the Command Window but I would like to still execute the catch block. I know there are ways to use MException and getReport, but from what I have been reading it seems that you need to know which potential errors that will be thrown so you can use an if statement to print your error. Here is the theoretical snippet of code that I would want to execute:

try
  % Here is a giant piece of code that can potentially
  % throw hundreds of errors
catch
  % If the above section threw an error, I want to display
  % whatever that error was and continue the script here
end

How would I go about printing the error statement that kicked the script out of the try block? Thanks,

- Matt

Answer 1

[Peter O]

Does the text need to remain red and halt execution?

A few ways to go about this. First the catch block will hold the error for you:

    try
       %Error-maker
    catch e %e is an MException struct
        fprintf(1,'The identifier was:\n%s',e.identifier);
        fprintf(1,'There was an error! The message was:\n%s',e.message);
        % more error handling...
    end

If you want the text red, switch fprintf from 1 (stdout) to 2 (stderr). If you want to throw the error again and stop execution after catching and handling it, use

    rethrow(e)

Does that help?

[Matt C]

Thanks, Peter! This is exactly what I had in mind. The stderr argument was an added benefit as well.

[Jeremy Ward]

Yeah thanks and kudos Peter. This is just what I needed.

[Paul Wintz]

Using fprintf(2, '<message>'); does not produce red text when used in a live script (on R2021b).