$NoValue
is a special value that can be assigned to an InitializationValue[…] object to indicate that the symbol referenced by the initialization value should be initialized with no value.
Details
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- Unsetting symbols during initialization is typically done with InitializationValue[sym]=$NoValue.
Examples
Wolfram Research (2017), $NoValue, Wolfram Language function, https://reference.wolfram.com/language/ref/$NoValue.html.
Text
Wolfram Research (2017), $NoValue, Wolfram Language function, https://reference.wolfram.com/language/ref/$NoValue.html.
CMS
Wolfram Language. 2017. "$NoValue." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/$NoValue.html.
APA
Wolfram Language. (2017). $NoValue. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/$NoValue.html