Name
missing value
Description
This is actually a class, but it has no values; all you’ll ever see is the class itself, so it works as if it were a constant. It seems to be a way for an application to return a value while signaling a nonvalue; it isn’t an error, and it isn’t a failure to return any value at all.
Example
tell application "Finder" to get clipboard -- missing value
In that example, the Finder’s dictionary implements
clipboard
but warns that it isn’t
yet available; getting its value is not an error on the
user’s part, but the Finder can’t
comply either, so the Finder needs a way to reply apologetically, and
missing value
is its solution.
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