About Saxon
Change history
Licensing
Configuration
Handling XML documents
Using XSLT
Using XQuery
Using XPath
Using XML Schema (XSD)
Streaming
The Gizmo utility
SaxonCS
Localization
Extensibility mechanisms
Saxon extensions
Experimental 4.0 extensions
Sample Saxon applications
Saxon SQL extension
Reference: XSLT elements
Reference: XPath syntax
- Constants
- Variable references
- Function calls
- Axis steps
- Parentheses and operator precedence
- Filter expressions
- Path expressions
- Simple mapping expressions
- Cast as, Treat as
- Set difference and intersection
- Union
- Arithmetic expressions
- Range expressions
- Comparisons
- Instance of and Castable as
- Conditional expressions
- Quantified expressions
- For expressions
- Let expressions
- Boolean expressions: AND and OR
- Sequence expressions
- New features in XPath 3.0
- New features in XPath 3.1
- Maps in XPath
- Arrays in XPath
Reference: Function library
Standards conformance
Using this documentation

Conditional expressions

XPath 2.0 introduced a conditional expression of the form if ( E1 ) then E2 else E3. For example, if (@discount) then @discount else 0 returns the value of the discount attribute if it is present, or zero otherwise.

It's also worth noting the coding pattern (@price, 5)[1] which returns the value of @price if it exists, or 5 otherwise.