∋ (contains as member)
Tests for set membership.
Syntax

A ∋ a

A
is a set 
a
is any object

Description
If a
is any object and A
a set, then A ∋ a
returns true
iff a
is an element of A
.
If the cardinality of A
is reasonably small, floatingpoint values are compared individually with epsilon. However, if the cardinality is very large, a different algorithm may be used to improve performance, which may not be epsilonbased.
The ∋
operator is implemented by the ContainsAsElement
function.
Examples
A ≔ {−1, 0, 1}
{1, −1, 0}
A ∋ sin(π)
true
See also

Set operators (list)