Assertion: unary predicate | /r/HasProperty | callable
Facets:
Source sentences:
text: A unary predicate must be callable.
text: A unary predicate must be callable, but need not necessarily be copyable, and must accept one argument and return a Boolean value.
text: A unary predicate must be callable and must accept one argument and return a Boolean value, but need not have any particular copy semantics.