For future reference, I found your spec unclear. In the end I settled on "2 parameters" as being the clearest statement. But it would help in the future if you gave sample test code using the function. Then there can be no doubt.

However if I am allowed to rearrange the arguments, I find it more natural that any special arguments should come first in the list. Giving a 38 character solution:

sub g {
(sort{abs$a-$_[0]<=>abs$b-$_[0]}@_)[1]
}
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