AskedQ
AskedQ["key"]
is a construct for use inside AskFunction that gives True if a value is currently associated with key, and False otherwise.
Examples
Wolfram Research (2016), AskedQ, Wolfram Language function, https://reference.wolfram.com/language/ref/AskedQ.html.
Text
Wolfram Research (2016), AskedQ, Wolfram Language function, https://reference.wolfram.com/language/ref/AskedQ.html.
CMS
Wolfram Language. 2016. "AskedQ." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/AskedQ.html.
APA
Wolfram Language. (2016). AskedQ. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/AskedQ.html