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FailureQ[expr]

gives True if expr has head Failure or is equal to $Failed or $Aborted.

Examples  
Basic Examples  
Properties & Relations  
Possible Issues  
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FailureQ

FailureQ[expr]

gives True if expr has head Failure or is equal to $Failed or $Aborted.

Examples

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Basic Examples  (1)

Test whether an expression represents a "failure":

Wolfram Language code: FailureQ[5]
Wolfram Language code: FailureQ[$Failed]

Select expressions that do not represent failure:

Wolfram Language code: Select[{a, $Failed, b, $Aborted, c, Failure["tag", <||>], d}, FailureQ[#] === False&]

Properties & Relations  (1)

$Failed is returned when an operation cannot be performed:

Wolfram Language code: FileByteCount["xxxx"]
Wolfram Language code: FailureQ[%]

Failure objects are returned by functions like Interpreter when they cannot produce a result:

Wolfram Language code: Interpreter["Integer"]["abc"]
Wolfram Language code: FailureQ[%]

$Aborted is returned when Abort[] executes or when the user manually aborts a computation:

Wolfram Language code: AbortProtect[Abort[]]
Wolfram Language code: FailureQ[%]

Possible Issues  (2)

The symbol Failure on its own does not represent failure:

Wolfram Language code: FailureQ[Failure]
Wolfram Language code: FailureQ[Failure["tag", <||>]]

Failure of a function to evaluate or the production of messages is not considered to represent failure:

Wolfram Language code: FailureQ[Take[{}, 5]]

Use Check to detect when an evaluation produces messages:

Wolfram Language code: Check[Take[{}, 5], $Failed]
Wolfram Language code: FailureQ[%]
Wolfram Research (2015), FailureQ, Wolfram Language function, https://reference.wolfram.com/language/ref/FailureQ.html.

Text

Wolfram Research (2015), FailureQ, Wolfram Language function, https://reference.wolfram.com/language/ref/FailureQ.html.

CMS

Wolfram Language. 2015. "FailureQ." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/FailureQ.html.

APA

Wolfram Language. (2015). FailureQ. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/FailureQ.html

BibTeX

@misc{reference.wolfram_2026_failureq, author="Wolfram Research", title="{FailureQ}", year="2015", howpublished="\url{https://reference.wolfram.com/language/ref/FailureQ.html}", note=[Accessed: 12-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_failureq, organization={Wolfram Research}, title={FailureQ}, year={2015}, url={https://reference.wolfram.com/language/ref/FailureQ.html}, note=[Accessed: 12-June-2026]}