Module transform 

The transformation engine.

A Transform performs processing, control flow, calculations, navigation, and construction to produce a Sequence. It starts with an initial context, the most important component of which is the current Item; this is often a Node that is the source document.

All functions in the Transform operate via the Node trait. This makes the transformation engine independent of the syntax of the source, stylesheet, and result documents. Any Nodes created by the transformation use the context’s result document object.

The following transformation implements the expression “1 + 1”. The result is (hopefully) “2”.

use xrust::value::Value;
use xrust::item::{Item, Node, Sequence, SequenceTrait};
use xrust::transform::{Transform, ArithmeticOperand, ArithmeticOperator};
use xrust::transform::context::{Context, StaticContext, StaticContextBuilder};

let xform = Transform::Arithmetic(vec![
        ArithmeticOperand::new(
            ArithmeticOperator::Noop,
            Transform::Literal(Item::<RNode>::Value(Rc::new(Value::from(1))))
        ),
        ArithmeticOperand::new(
            ArithmeticOperator::Add,
            Transform::Literal(Item::<RNode>::Value(Rc::new(Value::from(1))))
        )
    ]);
let mut static_context = StaticContextBuilder::new()
    .message(|_| Ok(()))
    .fetcher(|_| Ok(String::new()))
    .parser(|_| Err(Error::new(ErrorKind::NotImplemented, "not implemented")))
    .build();
let sequence = Context::new()
    .dispatch(&mut static_context, &xform)
    .expect("evaluation failed");
assert_eq!(sequence.to_string(), "2")

Modules

callable

Callables

context

Context for a transformation

numbers

These functions are for features defined in XPath Functions 1.0 and 2.0.

template

Templates

Structs

ArithmeticOperand

NameTest

NodeMatch

Enums

ArithmeticOperator

Axis

Grouping

Determine how a collection is to be divided into groups. This value would normally be inside an Option. A None value for the option means that the collection is not to be grouped.

KindTest

NodeTest

Order

The sort order

Transform

Specifies how a Sequence is constructed.

WildcardOrName

Functions

in_scope_namespaces

A convenience function to create a namespace mapping from a Node.