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IgnoringInactive[patt]

is a pattern object that, for purposes of pattern matching, ignores occurrences of Inactive in both patt and the expression being matched.

Examples  
Basic Examples  
Scope  
Applications  
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IgnoringInactive

IgnoringInactive[patt]

is a pattern object that, for purposes of pattern matching, ignores occurrences of Inactive in both patt and the expression being matched.

Examples

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Basic Examples  (1)

Replace all elements in a list that match a certain pattern:

Wolfram Language code: expr = {Sin[m], Inactive[Sin][p]}
Wolfram Language code: expr /. Sin[a_] -> t

Use IgnoringInactive to include a particular Inactive pattern:

Wolfram Language code: expr /. IgnoringInactive[Sin[a_]] -> t

Scope  (3)

By default, inactive symbols are excluded during pattern matching:

Wolfram Language code: expr = {Sin[m], Inactive[Sin][p]}
Wolfram Language code: Cases[expr, Sin[a_]]

Use IgnoringInactive to include a particular Inactive pattern:

Wolfram Language code: Cases[expr, IgnoringInactive[Sin[a_]]]

Find whether an expression matches a certain pattern:

Wolfram Language code: expr = Inactive[Sin][m]
Wolfram Language code: MatchQ[expr, Sin[a_]]

Include a particular Inactive pattern:

Wolfram Language code: MatchQ[expr, IgnoringInactive[Sin[a_]]]

Find whether an expression is free of a certain pattern:

Wolfram Language code: expr = Inactive[Sin][m]
Wolfram Language code: FreeQ[expr, Sin[a_]]

Include a particular Inactive pattern:

Wolfram Language code: FreeQ[expr, IgnoringInactive[Sin[a_]]]

Applications  (2)

Define a rule that applies to both active and Inactive objects:

Wolfram Language code: diff[IgnoringInactive[int[f_, x_]], x_] := f
Wolfram Language code: diff[int[Sin[x], x], x]

The rule also works for an inactive int:

Wolfram Language code: diff[Inactive[int][Sin[x], x], x]

Define a multiplication rule for the logarithm:

Wolfram Language code: IgnoringInactive[log[a_ b_]] := log[x] + log[y]

The rule works for both active and inactive versions:

Wolfram Language code: log[x y]
Wolfram Language code: Inactive[log][x y]
Wolfram Research (2014), IgnoringInactive, Wolfram Language function, https://reference.wolfram.com/language/ref/IgnoringInactive.html.

Text

Wolfram Research (2014), IgnoringInactive, Wolfram Language function, https://reference.wolfram.com/language/ref/IgnoringInactive.html.

CMS

Wolfram Language. 2014. "IgnoringInactive." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/IgnoringInactive.html.

APA

Wolfram Language. (2014). IgnoringInactive. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/IgnoringInactive.html

BibTeX

@misc{reference.wolfram_2026_ignoringinactive, author="Wolfram Research", title="{IgnoringInactive}", year="2014", howpublished="\url{https://reference.wolfram.com/language/ref/IgnoringInactive.html}", note=[Accessed: 12-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_ignoringinactive, organization={Wolfram Research}, title={IgnoringInactive}, year={2014}, url={https://reference.wolfram.com/language/ref/IgnoringInactive.html}, note=[Accessed: 12-June-2026]}