Method first

datafusion/physical-expr/src/projection.rs:1024–1027

Returns the first target expression and its index.

(&self)

impl ProjectionTargets {
    /// Returns the first target expression and its index.
    pub fn first(&self) -> &(Arc<dyn PhysicalExpr>, usize) {
        // Since the vector is non-empty, we can safely unwrap:
        self.exprs_indices.first().unwrap()
    }

    /// Adds a target expression and its index to the list of targets.
    pub fn push(&mut self, target: (Arc<dyn PhysicalExpr>, usize)) {