Struct Bound 

pub struct Bound<'a> {
    pub parts: Vec<(String, Option<&'a Value>)>,
    pub ctx: EvalCtx<'a>,
}

One row of a (possibly joined) result: an ordered list of (binding, row-or-NULL).

None is a LEFT JOIN’s unmatched side. Keeping it as None rather than an empty map is what makes n.nspname IS NULL answer correctly for a row that had no match — an empty map would report the column as absent, which looks identical but loses the distinction between “no such column” and “no matching row”.

Fields

parts: Vec<(String, Option<&'a Value>)>

ctx: EvalCtx<'a>

What this row may reach beyond itself — see EvalCtx.

Implementations

impl<'a> Bound<'a>

pub fn new(parts: Vec<(String, Option<&'a Value>)>) -> Self

A row with no enclosing scope and no way to run a subquery.