Module mem_query::col

Definition of fields for relational tuples.

At the very core of the memquery engine is the Col trait, and the col! macro that produces new column types that implement the trait.

Each Col is a transparent newtype that represents a single data cell in a relational table. It has very few methods of its own and Derefs to its inner type, so you can use a column cell in most places that expect the value stored there.

Traits

Col	A trait to represent a relation field
ColProxy	A value that stands in for a column