Method exists

datafusion/common/src/tree_node.rs:397–408

Returns true if `f` returns true for any node in the tree. Stops recursion as soon as a matching node is found

(&self, mut f: F)

    ///
    /// Stops recursion as soon as a matching node is found
    fn exists<F: FnMut(&Self) -> Result<bool>>(&self, mut f: F) -> Result<bool> {
        let mut found = false;
        self.apply(|n| {
            Ok(if f(n)? {
                found = true;
                TreeNodeRecursion::Stop
            } else {
                TreeNodeRecursion::Continue
            })
        })
        .map(|_| found)
    }

    /// Low-level API used to implement other APIs.
    ///