Struct GroupSpec 

pub struct GroupSpec {
    pub by: Vec<String>,
    pub aggs: Vec<(String, Agg)>,
    pub pre: Vec<(String, FExpr)>,
}

GROUP BY specification: grouping variables and result aggregates.

Fields

by: Vec<String>

Variables to group by (empty = single group over all solutions).

aggs: Vec<(String, Agg)>

(result_variable, aggregate) pairs.

pre: Vec<(String, FExpr)>

Synthetic per-row columns computed before grouping — (var, expr) for each aggregate whose argument is an expression rather than a bare variable (e.g. SUM(?a * 2) lowers to a hidden __aggN = ?a * 2, then SUM(__aggN)). Empty for the common case (aggregating a plain variable).

Trait Implementations

impl Clone for GroupSpec

fn clone(&self) -> GroupSpec

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for GroupSpec

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.