MissingQ

MissingQ[expr]

gives True if expr has head Missing.

Examples

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Basic Examples  (1)

Test whether an expression has head Missing:

Properties & Relations  (2)

Selecting values for which MissingQ gives False is equivalent to DeleteMissing:

Keys not present in an association will return Missing["KeyAbsent",]:

Use MissingQ to detect such results:

Possible Issues  (1)

MissingQ does not yield True for the symbol Missing itself:

Introduced in 2015
 (10.2)