wpo

Enable or disable wrap-only mode for an existing Type.

When wrap-only mode is enabled, no instances of the type can be created and the type can not be used by other type unless that type is also in wrap-only mode. The only purpose of a type in wrap-only mode is to wrap things with but this gives you the assurance that no data is created using this type.

Enable wrap-only mode

To enable wrap-only mode, make sure no instances of this type exist, and also be sure that no other type without wrap-only mode is dependent on the type you want to change. Loosely dependencies, like nillable ("Type?"), array-of ("[Type]") or set-of ("{Type}") dependencies are allowed.

Disable wrap-only mode

To disable wrap-only mode, make sure the type has no dependencies to type with wrap-only mode enabled. Loosely dependencies, like nillable ("Type?"), array-of ("[Type]") or set-of ("{Type}") dependencies are allowed.

Action

mod_type(type, 'wpo', mode)

Arguments

Argument	Type	Description
type	str	Name of the Type where to set the wrap-mode for.
'wpo'	str	Passing this argument will result in a set-wrap-mode action.
mode	bool	Enable or disable wrap-mode.

Return value

The value nil.

Example

This code shows the return value for the action wpo:

// Create type `Person`
set_type('Person', {
    name: 'str',
});

// Set type Person in wrap-only mode
mod_type('Person', 'wpo', true);

// Raises a type error
Person{};

Raises a type_err(): type Person has wrap-only mode enabled