Convert a flat array into a nested one in 1 pass and another…

Have an unpersisted base object, and nested_attributes_for already-persisted assocations

Checks for uniqueness vaidation in nested attributes for objects in memory .

A uniqueness validator for nested attributes. This gem solves the problem described in https://github.com/rails/rails/issues/4568.

Nested Attributes Validation Collection for Rails

Sort Nested Columns of tables in ruby

Based on ideas in http://exceptionalruby.com/ and the nestegg gem which does not support JRuby.

nested_file

Gem to conveniently handle multiple models in a single form. Rails 2 plugin by Ryan Bates converted into a gem.

nested_hash_tricks

JRuby include_package implementation that works across nested/inherited classes/modules

Find how deep is your array or hash.

A small ruby library which enables key/value lookups on deeply nested documents (Arrays and Hashes)

Utility methods such as deep_copy, dig, bury, delete, and path? for working with PORO structures arbitrarily nested with Hashes and Arrays.

DONT USE IT, NOT FINISHED - With a command, a scaffold will be done with all of his steps, but nested in a 1:n relation to another resource.

Parse multi-line string with indentation, return a structure where nesting is based on line indentation

Compose nested structs from hash/array structures.

Nested validations allow a parent's validity to include those of child attributes. Errors messages will be copied from the child attribute to the parent.

Access values hidden in deeply nested data structures with ease and without fear.

Nestene Automation Framework