isdef([],..) yields an error instead of returning []
Reported by Samuel GOUGEON (@sgougeon)
BUG DESCRIPTION:
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isdef([],..) yields an error instead of returning [].
This is disturbing, because each time we must include isdef(a) in
a conditional if a <> [] test, to secure it. This is not handy.
--> isdef([])
isdef: Wrong type for argument #1: Matrix of strings expected.
--> isdef([],"l")
isdef: Wrong type for argument #1: Matrix of strings expected.
ERROR LOG:
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HOW TO REPRODUCE THE BUG:
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isdef([])
isdef([],"l")
OTHER INFORMATION:
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