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CHAPTER
11
Functions
This section shows the general form of functions used in Pascal:
Subprograms
A
subprogram is a program unit/module that performs a particular task. These
subprograms are combined to form larger programs. This is basically called the 'Modular
design.' A subprogram can be invoked by a subprogram/program, which is called the
calling program.
Pascal provides two kinds of subprograms:
Functions: these subprograms return a single value.
Procedures: these subprograms do not return a value directly.
Functions
A function is a group of statements that together perform a task. Every Pascal program
has at least one function, which is the program itself, and all the most trivial programs can
define additional functions.
A function declaration tells the compiler about a function's name, return type, and
parameters. A function definition provides the actual body of the function.
Pascal standard library provides numerous built-in functions that your program can call.
For example, function AppendStr() appends two strings, function New() dynamically
allocates memory to variables and many more functions.
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