Partial exposure

[Waldek Hebisch]

Thinking loudy: I have noticed few times that tryning to generalize
various domains leads to trouble because interpreter picks
undesirable signatures. So we need some way to limit such
"inventions". We already have exposure, that completely
hides some constructors. But maybe we should have more detailed
control. For example consider constructor as exposed only
when arguments satisfy specific conditions? Or maybe hide
some signatures?

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Waldek Hebisch