Function pluck_annotation

prqlc/prqlc/src/sql/operators.rs:172–181

(
    annotation: &mut Vec<(String, pl::ExprKind)>,
    name: &str,
)

}

fn pluck_annotation(
    annotation: &mut Vec<(String, pl::ExprKind)>,
    name: &str,
) -> Option<pl::Literal> {
    annotation
        .pluck(|(n, val)| if n == name { Ok(val) } else { Err((n, val)) })
        .into_iter()
        .next()
        .and_then(|val| val.into_literal().ok())
}

/// Find the items in a `@{a=b}`. We're only using annotations with tuples;
/// we can consider formalizing this constraint.