Whether an expression asks bound(?name) anywhere inside it. BOUND is the only built-in whose grammar takes a bare Var, so it is the one reader a term may not be written into: bound(<ex://a>) is not a query.
bound(?name)
BOUND
Var
bound(<ex://a>)
The expression to read
The variable to look for
whether it is asked about
Whether an expression asks
bound(?name)anywhere inside it.BOUNDis the only built-in whose grammar takes a bareVar, so it is the one reader a term may not be written into:bound(<ex://a>)is not a query.