Basic Tutorial

Introduction

This tutorial is intended for users who already know at least one high level language such as lua or Python. WardScript claims to be simple and easy to learn, but it's recommended to have a basic knowledge on programming.

Variables

A variable name in wardscript can contain letters a-z, A-Z , numbers: 0-9, and a few special symbols: _ $ '.

a := 12;
b := a, c := b;

Data Types

There is only 4 data types in wardscript:

• Byte
• Nil
• Node
• Function

Byte

A byte is an unsigned integer lesser than 256

b1 := 0,
b2 := 255;

Nil

The Nil datatype represents the absence of value and is useful in data-structure implementation.

root := nil;

Note: nil is not a keyword, it's only a variable predefined in all programs

Node

In dynamic data structures, a node is a record that contains a data of interest and at least one pointer to reference to another node.

A node in wardscript is similar to a structure in c, but dynamically typed as in python or lua (dictionary and table), it differs from these by being immutable; which means that once a node is created, it can not have new members or eliminate those that already exist, only modify its content.

To create a node write a list of assignments (members) between curly brackets { }.

root := {
    data := 0,
    next := nil
};

To modify a member value

root.data := 1;

Function

Functions in wardscript are first-class values (wikipedia). To declare a function we must assign it to a variable. The syntax to declare a function is the following:

func arg1, arg2, arg3: result:
    ? Block of code ?
end

More examples:

f := func x, y: x:
    x := x + y;
end;

f2 := func x, y: nil:
    if x > y then
        present(x);
    else
        if y > x then
            present(y);
        else
            present(x, y);
        end
    end
end,

f2' := func x, y: nil:
    if x > y then
        present(x);
        exit;
    end

    if y > x then
        present(y);
        exit;
    end

    if x == y then
        present(x, y);
        exit;
    end;
end;

hello := func : nil:
    ? A function does not necessarily have to have arguments. ?
    print("Hello World!",10);
end;

Notes The argument list may be empty so the argument list won't take any argument at moment of call.

• The 'return variable' may or may not be declared inside the function body, but it has to exist in the scope at the momento of call. (an example is function f2)
• The 'exit' keyword it's like a return in the sense it breaks the flow of the function and the function return whatever the return variable has in that moment. (example of use in f2')

Control Flow

If clauses

Loops

A loop is equivalent to a while True or a while (1)

Essential functions

This is a list of very useful functions that are essential when programming.

• print

print(72, 101, 108, 108, 111, 32, 87, 111, 114, 108, 100, 33, 10);

? print is a built-in function that takes any number of arguments and prints the byte character.
 This would print out: "Hello world!" and a newline (because the last 10 represents a newline)
 print always returns nil ?

• present

a := 10, x := { data := 16 };
present(a, x, x.data, present, nil);
? present is a built-in function that takes any number of arguments and prints a human readable representation.
 This would print out: "10 <node at 0x23456789> 16 <function at 0x2248dd00> <nil> " and a newline 
 present always returns nil ?