Is there a shorter way to write compound 'if' conditions? [duplicate]

Answer 1

There is solution to your problem, not in language but in coding practices - Refactoring.

I'm quite sure that readers will find this answer very unorthodox, but - Refactoring can, and is used often to, hide a messy piece of code behind a method call. That method can be cleaned later or it can be left as it is.

You can create the following method:

private bool characterIsValid(char ch) {
    return (ch == 'A' || ch == 'B' || ch == 'C' || ..... );
}

and then this method can be called in a short form as:

if (characterIsValid(ch)) ...

Reuse that method with so many checks and only returning a boolean, anywhere.