System Feature
	conversion

Purpose
	Rules for coverting one data type to another

Syntax
	These type conversions are performed automatically.
	There is no explicit syntax.

Description
	When variables and constants of various types are
	intermixed in expressions. all types
	are converted to the type of highest operability.
	The following list shows the operability order.

	real	<----------- Highest operability
	int
	str
	bool	<----------- Lowest operability

	The following chart shows how the automatic
	conversion is performed.

	From			To
	------	------------------------------------------------------------------------------------------------------------------------------
		real	int	str	bool
		---------------	---------------	---------------	---------------
	real	-	Not applicable	Not applicable	Not applicable
	
	int	.0 is added to	-	Not applicable	Not applicable
		value

	str	0.0 if str is	0 if str is	-	Not applicable
		empty, else	empty, else 1
		1.0

	bool	0.0 if false,	0 if false,	"0.0" if false,	-
		else 1.0	else 1	else "1.0"	
		
Restrictions
	The above chart representations automatic conversions
	that are performed during evaluation of an expression
	that contains intermixed types. For conversions that
	are represented as 'Not applicable' in the above
	chart, see help page on make.

Valid Examples
	int i
	real x
	set $i=5
	set $x=10.0
	if ($i < $x)
		...
	$i will be converted to real during comparison.


Invalid Examples
	int i
	real x
	if ( ( $x ) AND ( $i < 7 ) )
		...
	Will produce an error, since an operand of
	AND operator is expected to be bool and
	$x can not be automatically converted to bool.

See Also
var
constant
make
makebool
makestr
makeint
makereal