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Chapter 9. Equality and identity

As in most language, one can distinguish between physical equality and logical equality.
Atomics can only be compared logically. Their physically identity is totally opaque to you.
Example 9.1. Logical comparison of two atomics
1 eq 1
Result (run with Zorba):
true

Example 9.2. Logical comparison of two atomics
1 eq 2
Result (run with Zorba):
false

Example 9.3. Logical comparison of two atomics
"foo" eq "bar"
Result (run with Zorba):
false

Example 9.4. Logical comparison of two atomics
"foo" ne "bar"
Result (run with Zorba):
true

Two objects or arrays can be tested for logical equality as well, using deep-equal(), which performs a recursive comparison.
Example 9.5. Logical comparison of two JSON items
deep-equal({ "foo" : "bar" }, { "foo" : "bar" })
Result (run with Zorba):
true

Example 9.6. Logical comparison of two JSON items
deep-equal({ "foo" : "bar" }, { "bar" : "foo" })
Result (run with Zorba):
false

The physical identity of objects and arrays is not exposed to the user in the core JSONiq language itself. Some library modules might be able to reveal it, though.