Nathan Shively-Sanders ee8986acc8 Error messages consistently use non- prefix ...

In the construction "x must either be y or non-y", we previously used "y
or not y", even y is always an adjective.

2016-02-22 14:16:00 -08:00

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reference

Error messages consistently use non- prefix

2016-02-22 14:16:00 -08:00