Evaluates to true when the wrapped pattern has at least one solution in the enclosing context,
without binding any of its variables outward. The clauses are space-joined into
a single group. Empty clauses, such as those produced by nil, are dropped first; when none survives, the
result is the empty fragment via nil, which callers must guard against where a pattern is required.
Generates a SPARQL
existsgraph-pattern test.Evaluates to
truewhen the wrapped pattern has at least one solution in the enclosing context, without binding any of its variables outward. The clauses are space-joined into a single group. Empty clauses, such as those produced by nil, are dropped first; when none survives, the result is the empty fragment via nil, which callers must guard against where a pattern is required.