The MPL Reference

This reference describes the Meta Programming Language (MPL) and its Standard Library.

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Question	Reference page	Scope
What syntax form is this?	Node Reference	Node syntax, scope behavior, stack effects, and node-specific semantics.
What schema or schema group is this value?	Schema Reference	Schema kinds, schema groups, and shared schema-level vocabulary.
What builtin performs this operation?	Built-in Reference	Language builtins, stack effects, constraints, and examples.
What Standard Library module provides this helper?	Standard Library Reference	Standard modules, exported helpers, and module-specific examples.
What exact grammar production accepts this text?	Grammar Reference	Railroad-diagram and W3C EBNF grammar snapshots.

Schema Reference: schema kinds, schema groups, and shared schema-level terms.
Grammar Reference: grammar snapshots in railroad-diagram and W3C EBNF form.
Node Reference: exhaustive syntax-node reference with examples.
Built-in Reference: exhaustive builtin reference with stack effects and dedicated pages.
Standard Library Reference: module index and dedicated module pages.