Type guard that checks whether a value is a Box produced by an inspect proxy's box() method. Identified by a private brand symbol so arbitrary { value, inspect } shapes in user data do not match.
box()
{ value, inspect }
The boxed value type
Value to check
True if the value is a Box
Type guard that checks whether a value is a Box produced by an inspect proxy's
box()method. Identified by a private brand symbol so arbitrary{ value, inspect }shapes in user data do not match.