SortableTree provides sorting of lists and hierarchies from ActiveAdmin index views.

A Ruby implementation of the Centered Interval Tree data structure. See also: http://en.wikipedia.org/wiki/Interval_tree

A Ruby implementation of the Augmented Interval Tree data structure. See also: http://en.wikipedia.org/wiki/Interval_tree

Sane ActiveRecord tree builder

Binary Tree based bracketing system

The Ruby Language Toolkit provides classes for creating context-free grammars, lexers, parsers, and abstract syntax trees.

A Ruby Gem implementation of Bitcoin HD Wallets

This is a ruby gem that provides drop in replacement for acts_as_tree but makes use of SQL recursive statement. Be sure to have a DBMS that supports recursive queries when using this gem (e.g. PostgreSQL or SQLite).

DataMapper plugin allowing the creation of tree structures from data models

RubyMacros is a lisp-like macro pre-processor for Ruby. More than just a purely textual substitution scheme, RubyMacros can manipulate and morph Ruby parse trees (in the form of RedParse Nodes) at parse time in just about any way you see fit. Macros are programmed in ruby itself. And since p...

Format your RSpec dots like a christmas tree!

Quick #rebuild! method implementation for closure_tree on PostgreSQL.

Generate CCN Treemap based on saikuro analysis

This gem provides the jQuery plugin jquery-treeview for your Rails 3.1 application.

acts_as_tree as a gem

Model gets: root, siblings, ancestors, descendants and other methods for tree navigation

Fully featured tree implementation for Mongoid using materialized paths and relative associations. Featuring Depth and Breadth first search.

Tree structures for ActiveRecord

Tree data structure for storing segments. It allows querying which of the stored segments contain a given point.

A self-balancing binary tree optimised for fast access to frequently used nodes. Useful for implementing caches and garbage collection algorithms.