GOSUB

The GOSUB command allows you to "jump" to a specific part of the program, execute a set of instructions and then return exactly to the point where you started.

It allows you to break a program into smaller, more manageable blocks of code, improving readability and maintenance. A subroutine can be called multiple times from different parts of the program, avoiding rewriting the same code multiple times. It helps organize the flow of the program, making it clearer and easier to follow.

While GOTO allows an unconditional jump to any line of the program, GOSUB is more structured and allows a return to the starting point. In general, GOSUB is considered a more powerful and flexible tool than GOTO, as it allows for better organization of the code.

It is possible to nest subroutines, but it is important to make sure that each GOSUB has its corresponding RETURN. So, a common mistake is to forget to put RETURN at the end of a subroutine, causing unpredictable behavior of the program.

Subroutines are often implemented through functions and procedures, which offer more advanced functionality and more rigorous management of variable scope.

EXAMPLE

 GOSUB leggiTasti

Used in:
USING GOSUB..RETURN (1) USING GOSUB..RETURN (2)