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Built-in Functions / Programming / Tests /

ValueQ

Usage

• ValueQ[expr] gives True if a value has been defined for expr, and gives False otherwise.


Notes

• ValueQ has attribute HoldFirst.
• ValueQ gives False only if expr would not change if it were to be entered as Mathematica input.
• See Section 2.3.5.
• See also: Information.
• New in Version 1.
Further Examples


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