BuildIterator optimizes the shape and builds a corresponding iterator tree.

IsNull safely checks if shape represents an empty set.

One checks if Shape represents a single fixed value and returns it.

Optimize applies generic optimizations for the tree.

Walk calls provided function for each shape in the tree.

TODO: tune.

AllNodes represents all nodes in QuadStore.

Comparison is a value filter that evaluates binary operation in reference to a fixed value.

Count returns a count of objects in source as a single value.

Except excludes a set on nodes from a source.

Filter filters all values from the source using a list of operations.

FixedTags adds a set of fixed tag values to query results.

InternalQuad is an internal representation of quad index in QuadStore.

IntersectOpt is like Intersect but it also joins optional query shapes to the main query.

Materialize loads results of sub-query into memory during execution to speedup iteration.

NodesFrom extracts nodes on a given direction from source quads.

Null represent an empty set.

Page provides a simple form of pagination.

QuadFilter is a constraint used to filter quads that have a certain set of values on a given direction.

QuadsAction represents a set of actions that can be done to a set of quads in a single scan pass.

Regexp filters values using regular expression.

Save tags a results of query with provided tags.

Unique makes query results unique.

Wildcard is a filter for string patterns.

Composite shape can be simplified to a tree of more basic shapes.

QuadIndexer is an optional interface for quad stores that keep an index of quad directions.

Shape represent a query tree shape.

ValueFilter is an interface for iterator wrappers that can filter node values.

Fixed is a static set of nodes.

Intersect computes an intersection of nodes between multiple queries.

Lookup is a static set of values that must be resolved to nodes by QuadStore.

Quads is a selector of quads with a given set of node constraints.

Union joins results of multiple queries together.

WalkFunc is used to visit all shapes in the tree.