Design issues of subprogram

Subprogram:

A subprogram means a function or procedure.

For example

void main()
{
}

int show()
{
}

Some of the design issues of subprogram are:

• Are local variables static or dynamic?
• Can subprogram definitions appear in other subprogram definitions?
• What parameter-passing method or methods are used?
• Are the types of the actual parameters checked against the types of the formal parameters?
• If subprograms can be passed as parameters and subprograms can be nested, 
• what is the referencing environment of a passed subprogram?
• Can subprograms be overloaded?
• Can subprograms be generic?
• If the language allows nested subprograms, are closures supported?

Some definitions to be know:

1. An overloaded subprogram

An overloaded subprogram is one that has the same name as another subprogram in the same referencing environment. 

2. A generic subprogram

A generic subprogram is one whose computation can be done on data of different types in different
calls.

3. A closure

A closure is a nested subprogram and its referencing environment, which together allow the subprogram to be called from anywhere in a program.