Type

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Datatype declaration

Definition

Type <name>

<variables>

End

Creates a new datatype. It's handled as if it were a struct, so the declared variables are members of the struct.

While it's a convention to use a '_' as first character in the name of a datatype, it's not mandatory.

When used as an argument in a function or process, the parameter is not a copy, but the variable itself, as shown in the first example, and any change made to the parameter is also changed in the argument. It's more elegant to use a pointer though, as it also displayed.

Example

A file with name and path. Note that the assignment myFile2 = myFile; makes a copy of myFile and throws it into myFile2, which is normal. But when it's used as an argument in a function, the parameter is not a copy but the _file itself.

Type _file
    String path;
    String name;
End

Process Main()
Private
    _file myFile;
    _file myFile2;
Begin

    myFile.path = "C:\";
    myFile.name = "autoexec.bat";
    say("1: " + myFile.path + myFile.name);

    myFile2 = myFile;
    myFile2.name = "config";
    say("1: " + myFile.path + myFile.name);
    say("2: " + myFile2.path + myFile2.name);

    setName(myFile,"pagefile");
    say("1: " + myFile.path + myFile.name);

    setName2(&myFile2,"pagefile");
    say("2: " + myFile2.path + myFile2.name);

    Repeat
        frame;
    Until(key(_ESC))

End

Function setName(_file f, string name)
Begin
    f.name = name;
End

Function setName2(_file* f, string name)
Begin
    f.name = name; // this is actually (*f).name = name, but . can be used like this
End

Used in example: say(), key(), Pointer

This will result in something like:

Type3.PNG
Type results


A point with x and y.

// Declare the type _point
Type _point
    float x;
    float y;
End

// Declare the function distance(), because the function returns a datatype
// other than int, so it needs to be declared before usage.
Declare float distance(_point a,_point b)
End

Process Main()
Private
    _point p1,p2;
Begin

    p1.x = 15.3;
    p1.y = 34.9;
    p2.x = 165.4;
    p2.y = 137.2;

    write(0,0,0,0,"Distance: " + distance(p1,p2));
    drw_line(p1,p2);

    Repeat
        frame;
    Until(key(_ESC))

End

Function float distance(_point a, _point b)
Begin
    return sqrt( (a.x-b.x)*(a.x-b.x) + (a.y-b.y)*(a.y-b.y) );
End

Function int drw_line(_point a, _point b)
Begin
    return draw_line( a.x , a.y , b.x , b.y );
End

Used in example: write(), key(), sqrt(), draw_line()

This will result in something like:

Type.PNG
A line and its distance

ProcessType

Definition

Type <processname>

Acquires the processTypeID of a processType or function. This can be useful for example with the functions get_id() and signal().

Example

Program example;
Private
    proc proc_id; //int could be used too
Begin

    // Start 3 proc's
    proc();
    proc();
    proc();

    // Display all alive proc's
    y = 0;
    while( (proc_id=get_id(type proc)) )
        write(0,0,(y++)*10,0,"proc: " + proc_id);
    end

    // Wait for key ESC
    Repeat
        frame;
    Until(key(_ESC))

End

Process proc()
Begin
    Loop
        frame;
    End
End

Used in example: get_id(), write(), key()

This will result in something like:

Type2.PNG
A list of active proc's