Structure of a program

A NeoObjectPascal program has three parts, all optional except the ending:

1. A uses clause (module imports), terminated by ;.
2. Zero or more declarations (variables, functions, classes, interfaces, tests), each terminated by ;.
3. A main block begin ... end. — the final period . ends the program.

uses internal.string;

var mensagem: String;

function emMaiusculas(s: String): String
begin
    return toUpperCase(s);
end;

begin
    mensagem := emMaiusculas("olá");
    WriteLn(mensagem);
end.

Saída

 OLÁ 

No program header

Unlike some Pascal dialects, NeoObjectPascal does not use a program Name; header. The program starts directly with the uses clause, the declarations, or the begin block.

The main block

The begin ... end. block contains the statements executed when the program runs. Each statement ends with a semicolon ;:

begin
    WriteLn("primeira linha");
    WriteLn("segunda linha");
end.

Note the final period after the end that closes the program — it is mandatory. Inner blocks (of functions, loops, etc.) end with just end (no period).

Comments

NeoObjectPascal has only single-line comments, started by //:

begin
    // This is a comment
    WriteLn("Oi"); // also works at the end of a line
end.

No block comments

There are no { ... } or (* ... *) comments. Curly braces { } are reserved for Java code blocks.

Declarations at the top vs. inside the block

You can declare variables both at the top of the file and inside a block:

var x: Integer;   // top-level declaration

begin
    x := 10;
    var y: Integer;   // declaration inside the block
    y := 20;
    WriteLn(x + y);
end.

Saída

 30 

With the structure in place, head over to Variables and types.