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Equality and inequality expressions
return the result of an equality comparison of its operands.
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Expression
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Character representation
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Returns
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Equality
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== eq
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True (1) when both operands compare identically,
and false (0) if they do not compare identically.
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Inequality
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<> ne
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True (1) when both operands do not compare
identically, and false (0) if they compare identically.
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The following special cases also apply when using equality operators:
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If either operand is null, a null comparison is performed.
Null-valued operands compare identically whenever both operands
are null, and compare differently whenever one operand is not null.
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If both operands are references, both operands compare identically
when they both refer to the same object, and compare differently
when they do not refer to the same object.
-
If both operands are string valued, a locale-sensitive lexicographic
string comparison is performed on the operands. Otherwise, if they
are not both null, the operands are promoted to numeric values,
and a numeric comparison is performed.
These are examples of using the equality and inequality expressions:
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Expression
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Returns
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3 == 3
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1
(true)
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3 <> 4
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1
(true)
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"abc" eq "def"
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0
(false)
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"def" ne "abc"
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1
(true)
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5 + 5 == 10
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1
(true)
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5 + 5 <> "10"
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0
(false)
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