ValidatesTimeliness mongoid ORM compatability.

Parse numbers suffixed with mangitude specifiers and/or abbreivations.

Library for validating unchangeable attributes.

Validates if an attribute has a valid xml content or a xsd valid content.

Validate XML against it's embedded XSI elements that define the XSD's.

Adds validation methods considering different country zip code formats. Currently, we can validate 130 countries.

Delegates validation between objects

Find and report ActiveRecord validation errors.

Hints for validation.

Helper to customize the validation messages in Hanami application views.

If you need a way to easily skip validations on some attributes and only in certain cases, this gem will allow you to do it in a clean and elegant way.

A extension activemodel's validations to validation step by step.

Checks whether an ActiveModel Validator is attached to an attribute of a Model and with which options

extension for active_record

Rails 3 generator plugin that generates validator's skeleton files.

Validação de inscrição estadual dos 26 estados federativos

Allow validate uniqueness across multiple column

An implementation of several error checking algorithms,including Luhn and Damm.

contextual validations for controllers and wanna learn to do other stuff good too

ActiveModel validation for credit card number.