Comparisons
The simplest comparison operators are eq
, ne
, lt
le
, gt
, and ge
. These compare two atomic values of
the same type, for example two integers, two dates, or two strings. In the case of strings,
the default collation is used (see DEFAULT_COLLATION
in Configuration Features). If the operands are
not atomic values, an error is raised.
The operators =
, !=
, <
, <=
,
>
, and >=
can compare arbitrary sequences. The result is
true if any pair of items from the two sequences has the specified relationship, for
example $A = $B
is true if there is an item in $A
that is equal
to some item in $B
. If an argument is a node, the effect depends on whether
the source document has been validated against a schema. In Saxon-EE, with a validated
source document, Saxon will use the typed value of the node in the comparison. Without
schema validation, the type of the node is untypedAtomic
, and the effect is
that the value is converted to the type of the other operand.
The operator is
tests whether the operands represent the same (identical)
node. For example, title[1] is *[@note][1]
is true if the first
title
child is the first child element that has a note
attribute. If either operand is an empty sequence the result is an empty sequence (which
will usually be treated as false).
The operators <<
and >>
test whether one node
precedes or follows another in document order.