Quantified edges

An edge quantifier repeats the edge pattern. Bounds count edges, not nodes.

MATCH p = (a {name: 'Alice'})-[edges:Knows]->{0,2}(b)
RETURN b.name AS destination, PATH_LENGTH(p) AS hops ORDER BY hops;

This returns Alice/0, Bob/1 and Cara/2. A zero-hop match applies both endpoint constraints to the same node. Intermediate nodes are not implicitly constrained by the endpoint’s labels or properties.

Quantifier	Repetitions
{m}	Exactly m
{m,n}	From m through n
{m,}	At least m
{,n}	Zero through n
*	Zero or more
+	One or more

An explicit upper bound must be positive. Unbounded forms require the planner to prove a finite complete search for the chosen mode/selector; unsupported cases return an error. Search limits are checked against the required bound, rather than silently truncating paths.

A quantifier after a simplified path repeats the whole slash pattern. -/E F/->{2} is two E-then-F sequences, not one E and two F edges. -/L|R/->{1,2} may mix the labels from one repetition to the next. A quantifier written on a label stays on that edge and does not discard the outer quantifier. Repeating a slash pattern whose minimum length is zero is rejected, because the repeated primary would not make progress.

A selective search (ANY, SHORTEST, or a shortest-length group) of one homogeneous unbounded edge stops at a complete hop bound derived from the node count and the number of paths requested. That search does not enumerate every trail out to the edge count. ALL keeps the match mode’s own limit.

An anonymous unconstrained start of a quantifier whose lower bound is at least one, such as ()-[:Knows]->+(), reads that edge directly. It does not first cross-join every node to recover a source the edge already stores. Naming, labeling, or otherwise constraining the start still reads the node tables. A quantifier that allows zero repetitions, including * and {0,n}, still anchors on every node so a node with no matching edge can produce the empty walk.

The edges variable above is an ordered list outside the repeated segment. Within an edge predicate it denotes the current edge. Zero repetitions expose an empty list. Group declarations must be fresh.

MATCH (a {name: 'Alice'})-[edges:Knows]->{2}(b)
FOR edge IN edges
RETURN ELEMENT_ID(edge) AS id;