XSLT 2.0 reference

XSLT | expressions

!= | > | >> | >= | < | << | <= | (::) | * | + | | − | . | .. | ⁄⁄ | = | @ | [] | and | cast as | castabel as | div | eq | every..in..satisfies | except | for..in..return ge | gt | idiv | if..then..else | instance of | is | le | lt | mod | ne | or | some..in..satisfies | to | treat as | | union | | |

Not Equal. General comparisons are existentially quantified comparisons that may be applied to operand sequences of any length. When evaluating a general comparison in which either operand is a sequence of items, an implementation may return true as soon as it finds an item in the first operand and an item in the second operand that satisifies the condition. != is not inverse of =.

Example 1:

Input:	(1, 2) != (2, 3)
Output:	true

Example 2:

Input:	(2, 3) != (3, 4)
Output:	true

Example 3:

Input:	(1, 2) != (3, 4)
Output:	true

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XSLT 2.0 reference