Construction forms

Typical construction forms differ only by the mutability of the schema supplier closure.

myRef: @getSchema Mref;        # mutable result from CALL
myRef: [getSchema Cref] Mref;  # immutable result from CALL

getSchema is one helper that returns one representative value or reference of the required schema.

Stored address model

• data stores one address as Natx.
• CALL reconstructs the referenced value from that address through getSchema and addressToReference.
• set replaces only the stored address. The wrapper does not copy or own the target object.

Lifetime boundary

• Mref never destroys or frees the stored target object.
• Later CALL requires the target object to remain valid at the stored address.
• Mutable wrappers return mutable results. Immutable wrappers return immutable results.

Methods

Fields

• SCHEMA_NAME: reported schema name, "Mref".
• getSchema: helper used to reconstruct the target schema.
• data: stored address as Natx.

Examples

Mutable and immutable wrappers

"Mref" use
"control" use

Int32Schema: [0];

{} () {} [
  value: 5;

  mutableHolder: @Int32Schema Mref;
  @value @mutableHolder.set
  mutableHolder printStack _:;

  immutableHolder: [Int32Schema Cref] Mref;
  @value @immutableHolder.set
  immutableHolder printStack _:;
] "main" exportFunction

Expected Output During Compilation

Int32 Ref
Int32 Cref

Runtime example

"Mref" use
"String" use
"control" use

Int32Schema: [0];

{} Int32 {} [
  value0: 5;
  value1: 9;
  holder: @Int32Schema Mref;
  @value0 @holder.set
  ("first=" holder new LF) printList
  @value1 @holder.set
  ("second=" holder new LF) printList
  0
] "main" exportFunction

Expected Output

first=5
second=9

See also

• Owner: Ownership management and move/transfer semantics.
• addressToReference builtin (address modelValue -- reconstructedValue) Builds a typed result from a numeric address and a model value that supplies schema and mutability.
• storageAddress builtin (value -- address) Returns the storage address of one non-Meta value as Natx.
• Ref: Reference schema kind whose exact schema also includes the target schema and mutability.