Dynamicprivate

Dynamicprivate is a term used in discussions of programming language design to describe a proposed mechanism for combining dynamic binding with private access control. It refers to a visibility rule where a member marked as dynamicprivate is only accessible within the dynamic call chain that originates from the defining scope, rather than being universally private to a class or module or accessible through unrelated execution paths.

In a language that implements dynamicprivate, access to such members is determined at runtime based on the dynamic invocation context. A dynamic private member would be visible to code invoked through a chain of calls that includes the defining scope, but would be invisible to code reached through external or non-dynamic paths. This contrasts with lexical private access, which is determined solely by static source locations, and with ordinary runtime private access, which may be enforced differently depending on the language.

Dynamicprivate is primarily discussed as a conceptual mechanism for dynamic or plug-in environments, sandboxing, and dynamic composition scenarios. Potential use cases include allowing internal state to be shared during a controlled dynamic extension of behavior while preventing leakage through static interfaces or unrelated modules.

Critiques of dynamicprivate focus on complexity and predictability. Because access is tied to dynamic call sequences, reasoning about visibility can become difficult, and performance overhead may occur due to runtime checks. Debugging dynamicprivate access failures can also be challenging, especially in large or deeply nested call stacks.

Dynamicprivate remains a proposed or hypothetical feature rather than a widely adopted language construct. It is frequently mentioned alongside other access-control strategies such as lexical private, protected, module-private, and dynamic scoping, as researchers and language designers explore trade-offs in privacy, flexibility, and safety.