NotRequiredRequired

NotRequiredRequired is a term used in software design to describe a conditional validation constraint in which a field, parameter, or option is not required by default but becomes required under certain circumstances. The concept is used to balance flexibility with data integrity, allowing optional inputs that can be escalated to mandatory when related data is present or a particular mode is activated. The term signals a paradox: something that is not required, yet in practice must be provided in some contexts.

Origin and usage context: NotRequiredRequired emerged in discussions of form validation, API schemas, and configuration systems as a descriptive label for conditional requirements. It does not refer to a language feature but to a pattern where the necessity of input depends on other inputs or settings. It is most common in domains that aim to collect minimal data while still ensuring complete information for specific workflows.

Characteristics and implementation: The pattern applies to fields, parameters, or options that are optional by default but can be mandated by a secondary condition. Implementations typically involve conditional validators, dependent rules, or schema constructs that express if-then-else logic. In JSON Schema, for example, conditional dependencies or if/then/else constructs can enforce a field’s presence when related criteria are met. In user interfaces, dynamic validation messages and adaptive UI prompts help communicate when a previously optional field becomes required.

Examples: A user profile form may treat a “billingAddress” field as NotRequiredRequired, becoming mandatory if the user checks a “hasBillingAddress” box. An API may require a “secondaryEmail” only when a “requireSecondaryContact” flag is true.

Reception and considerations: While useful for flexible data collection, NotRequiredRequired can confuse users if rules are unclear. Clear messaging, consistent behavior, and thorough testing are advised. See also: conditional validation, dependent fields, required vs optional.