new set.Algebra(compares...)

An algebra instance can perform a variety of set logic methods using the compares configuration.

A default algebra instance can be created like:

import set from "can-set";
const defaultAlgebra = new set.Algebra();

This treats every property as a filter in a where clause. For example:

// `{id: 2, ownerId: 5}` belongs to ``.getList({ownerId: 5})`
defaultAlgebra.has( { ownerId: 5 }, { id: 2, ownerId: 5 } ); //-> true

defaultAlgebra.getSubset( { ownerId: 5 }, {},
    [
        { id: 1, ownerId: 2 },
        { id: 2, ownerId: 5 },
        { id: 3, ownerId: 12 }
    ] ); //-> [{id: 2, ownerId: 5}]

Compares configurations can be passed to add better property behavior awareness:

import set from "can-set";
const todoAlgebra = new set.Algebra(
    set.props.boolean( "completed" ),
    set.props.id( "_id" ),
    set.props.offsetLimit( "offset", "limit" )
);

defaultAlgebra.getSubset( { limit: 2, offset: 1 }, {},
    [
        { id: 1, ownerId: 2 },
        { id: 2, ownerId: 5 },
        { id: 3, ownerId: 12 }
    ] ); //-> [{id: 2, ownerId: 5},{id: 3, ownerId: 12}]

<a href="can-set.props.html" title="Contains a collection of prop generating functions. The following functions create compares objects that can be mixed together to create a set Algebra. import set from "can-set"; const algebra = new set.Algebra( {

    // ignore this property in set algebra
    sessionId: function() {
        return true;
    }
},
set.props.boolean( "completed" ),
set.props.rangeInclusive( "start", "end" )

);">props has helper functions that make common Compares configurations.