XPath:Functions:boolean

From MDC

Contents 1 Syntax 2 Arguments 3 Returns 4 Notes 5 Defined 6 Gecko support

The boolean function evaluates an expression and returns true or false.

[edit] Syntax

boolean( expression )

[edit] Arguments

expression

The expression to be evaluated. The expression can refer to numbers and node-sets as well as booleans.

[edit] Returns

Boolean true or false after evaluating expression.

[edit] Notes

• A number evaluates to false if it is positive or negative zero or NaN. Otherwise, it evaluates true.
• A node-set evaluates to true if it is non-empty.
• A string evaluates to false if it an empty string. Otherwise, it evaluates to true.
• An object of a type other than the four basic types is converted to a boolean in a way that is dependent on that type.

[edit] Defined

XPath 1.0 4.3

[edit] Gecko support

Supported.