Data Types

iXML is a loosely typed language where the data type of a variable is often determined by the context in which it is used. However, the underlying runtime recognizes distinct intrinsic data types, and understanding them is essential for avoiding common bugs.

Type system overview

XML does not know intrinsic data types — in iXML, textual content is string by default unless converted by context or explicit cast. This is one of the most important facts for new iXML developers:

XML

<set var="x">42</set>        <!-- "42" is a string -->
<cast var="x" type="int" />  <!-- now 42 is an integer -->

The <set> command always produces a string. If your logic depends on numeric or boolean behavior, you must cast explicitly with cast or rely on automatic evaluation in contexts that expect a specific type (like int attributes).

Available types

iXML recognizes nine types, divided into primitive (assigned by value) and complex (assigned by reference):

Type	Category	Neutral Literal	Description
null	Primitive	NULL	Absence of a meaningful value
bool	Primitive	FALSE	Truth value (TRUE or FALSE)
int	Primitive	0	Whole number without fractional part
float	Primitive	0.0	Number with fractional part
string	Primitive	'' (empty)	Byte sequence or Unicode characters
array	Complex	—	Ordered key-value collection
function	Complex	—	Closed subroutine with local context
macro	Complex	—	Open subroutine in caller's context
class	Complex	—	Array prototype for OOP

Use typeof to inspect a variable's type at runtime:

XML

<set var="x">42</set>
<typeof var="x" var_result="t" />
<output>$t</output>
<!-- string -->

Detailed type guides

• Strings — the default type, string operations, and encoding
• Numbers — integers, floats, arithmetic context, and notation
• Booleans — truth values, truthiness rules, and comparison behavior
• Null and Undefined — the difference between null, undefined, and empty
• Arrays — ordered key-value collections, the primary complex type
• Type Conversion — casting rules, comparison behavior, and the conversion table