privatevarvm

privatevarvm is a term used in discussions of virtual machine design to denote a mechanism or concept for handling private variables within a runtime environment.

Etymology and usage: It is a portmanteau of private, var, and VM. It is not a formal standard; occurrences are sparse and typically appear in academic papers, design notes, or code comments illustrating privacy enforcement in VMs.

Concept and implementation: In a privatevarvm-style model, private variables are allocated in a distinct memory region or access-controlled object space. Access to these variables from user code is mediated by the VM's runtime and by access control metadata; direct memory addresses are detached from conventional program variables.

Impact: Benefits include stronger encapsulation and memory safety; potential overhead from additional indirection and metadata; possible compatibility issues with languages that rely on direct memory sharing.

Relation to existing concepts: Similar ideas exist in object-capability models, private fields in high-level languages, and sandboxed execution environments. The term privatevarvm is not widely standardized; consult project or language documentation for precise meaning.