Type-constrained operations for plug-in types

A system comprising:

• at least one device including a hardware processor;
• the system being configured to perform operations comprising:
• encountering, by a runtime environment, a request to perform a type-constrained operation that requires evaluating a type constraint associated with a particular plug-in type,
• wherein the runtime environment comprises native instructions capable of evaluating type constraints associated with a system of built-in types supported by the runtime environment, and
• wherein the runtime environment lacks sufficient native instructions to evaluate type constraints associated with plug-in types defined outside of the system of built-in types;
• accessing, by the runtime environment, a plug-in type framework to obtain a particular type descriptor instance associated with the particular plug-in type,
• wherein the plug-in type framework is designated, prior to encountering any request to perform the type-constrained operation, to obtain type descriptor instances for the runtime environment,
• wherein the type descriptor instances define, to the runtime environment, constraints on plug-in types to an extent that any such constraints exist, and
• wherein the particular type descriptor instance defines a particular type constraint that does not match any single built-in type in the system of built-in types;
• and
• performing, by the runtime environment, the type-constrained operation, wherein performing the type-constrained operation comprises using the particular type descriptor instance to evaluate the particular type constraint associated with the particular plug-in type.

A method comprising:

• encountering, by a runtime environment, a request to perform a type-constrained operation that requires evaluating a type constraint associated with a particular plug-in type,
• wherein the runtime environment comprises native instructions capable of evaluating type constraints associated with a system of built-in types supported by the runtime environment, and
• wherein the runtime environment lacks sufficient native instructions to evaluate type constraints associated with plug-in types defined outside of the system of built-in types;
• accessing, by the runtime environment, a plug-in type framework to obtain a particular type descriptor instance associated with the particular plug-in type,
• wherein the plug-in type framework is designated, prior to encountering any request to perform the type-constrained operation, to obtain type descriptor instances for the runtime environment,
• wherein the type descriptor instances define, to the runtime environment, constraints on plug-in types to an extent that any such constraints exist, and
• wherein the particular type descriptor instance defines a particular type constraint that does not match any single built-in type in the system of built-in types;
• and
• performing, by the runtime environment, the type-constrained operation, wherein performing the type-constrained operation comprises using the particular type descriptor instance to evaluate the particular type constraint associated with the particular plug-in type,
• wherein the method is performed by at least one device comprising a hardware processor.