Variables

A variable is a symbolic name for a value.

There are two basic properties of a variable:

Scope, which specifies the range of the environment in which the variables can be referenced.
Datatype

There are two kinds of variables:

Port variables
Component variables

Port Variables

The values of the port structure are referenced as port variables within a component. There are automatic port variables for both input ports and output ports. Port variables are valid within the component, and they inherit the name and datatype of the port structure. The name of the variable is prefixed with "IN." for the input ports and "OUT." for the output ports. input port variables are read-only, but output port variables can be written.

This example uses port variables in an expression:

uUpper(IN.CU_NAME)

This example uses port variables in a procedure:

OUT.CU_NAME = uUpper(IN.CU_NAME);

Component Variables

Component variables are associated with component properties and represent the current evaluated property content. You can reference these variables inside the component. The name of the variable is prefixed with “REF.” For example:

uIsNull(REF.Host)

To provide flexibility in transformations, all port and component variables internally use the datatype string. If you use numeric values, this may result in unexpected behavior.

If multiplied by 1, the numeric value of a string variable is used in a calculation:

IN.Margin="2", IN.Price="10"
IN.Margin>IN.Price  - returns TRUE

To enforce a numeric comparison, use:

IN.Margin*1>IN.Price*1  - returns
FALSE

Do not use reserved JavaScript keywords for port and component variable names:

Reserved JavaScript Keywords
break	case	catch	continue	default
delete	do	else	finally	for
function	if	in	instanceof	new
return	switch	this	throw	try
typeof	var	void	while	with
abstract	boolean	byte	char	class
const	debugger	double	enum	export
extends	final	float	goto	implements
import	int	interface	long	native
package	private	protected	public	short
static	super	synchronized	throws	transient
volatile	const	export