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Numeric literals

Here, the function named

sum()

takes two parameters of type

Integer

and returns an

Integer

(as

indicated by the semicolon after the closing parenthesis). If the function doesn’t return a value, it is

defined as type

Void

function doNothing(num1 : Integer, num2 : Integer) : Void {

num1 + num2;

}

Functions that have argument and return value types defined are type checked, although it is possible to

leave off the types and have functions behave as they do in ECMAScript today.

Netscape’s proposal would make overloading of functions work in a manner similar to overloading in

Java: Just define as many functions as necessary with different argument lists. For example, you could

make two different versions of the

sum()

function defined earlier, one to take two arguments and one to

take three:

function sum(num1 : Integer, num2 : Integer) : Integer {

return num1 + num2;

}

function sum(num1 : Integer, num2 : Integer, num3 : Integer) : Integer {

return num1 + num2 + num3;

}

Another change to functions is the capability to define named arguments, which are optional and can be

assigned in any order so long as the name of the argument is used. For example, the following function

contains two named arguments:

function sum(num1 : Integer, num2: Integer, named num3 : Integer = 7, named num4 :

Integer = 10) {

return num1 + num2 + num3 + num4;

}

To call this function, you can use only two arguments, three arguments, or all four:

result = sum(10, 20);

result = sum(10, 20, num3: 10);

result = sum(10, 20, num4: 10, num3: 20);

Note the last two lines where the named arguments are used; specifically notice the last line, where

num4

is used before

num3

Numeric literals

In order to support more types of numbers, the Netscape proposal introduces three new types of num-

bers: long, unsigned long (ulong), and float. You can indicate the type of number by including an

(or

)

for long values,

(or

) for ulong values, and

(or

) for float values. For example,

L25

is a

long,

UL25

is a ulong, and

F25

is a float.

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