overload (--)

Inputs

• None.

Outputs

• None.

overload creates a pending overload specifier in the current scope.

That pending specifier is consumed by the next successful local creation. Intervening operations do not consume it.

A public overload can be selected directly by module loading. A private overload participates in same-name lookup only after its module has already been loaded through some other public name.

Behavior

• The builtin has no inputs and no outputs.
• If another overload specifier is already pending in the same scope, using overload again is invalid.
• After the next successful local creation, the pending overload specifier is cleared.
• A pending overload specifier is invalid for importVariable.
• If the scope ends before the pending overload specifier is consumed, the program is invalid.
• Pending private or virtual coexist with the pending overload specifier.

Example

overloadExample.mpl

private overload virtual hiddenHelper: 3;
overload virtual helper: 1;
virtual publicAgain: 2;

test.mpl is the primary runnable example file. indirectLookupExample.mpl records the separate lookup case after module loading through another public name.

test.mpl

"overloadExample.helper" use

{} 0 {} [
  "-- directly selected public overload --" printCompilerMessage
  helper printStack _:;
  0
] "main" exportFunction

indirectLookupExample.mpl

"overloadExample.publicAgain" use

{} 0 {} [
  "-- following created name is public --" printCompilerMessage
  publicAgain printStack _:;

  "-- public overload still participates in lookup --" printCompilerMessage
  helper printStack _:;

  "-- private overload also participates after module load --" printCompilerMessage
  hiddenHelper printStack _:;

  0
] "main" exportFunction

Module-loading wrapper lines are omitted below.

Expected Output During Compilation

-- directly selected public overload --
1
-- following created name is public --
2
-- public overload still participates in lookup --
1
-- private overload also participates after module load --
3

See also

• NAME: ...; node — Pushes a name onto the name stack and creates a local by consuming that name and one data-stack value.
• def builtin (value name --) Creates a named local or field using a known Text name.
• exportFunction builtin (inputsSchema output options callable name --) Exports a named function built from a Block and a signature; pending overload applies there.
• importFunction builtin (inputsSchema output options name --) Declares or imports a named function with the supplied signature; pending overload applies there.
• importVariable builtin (schema name --) Creates a local that refers to external variable storage; pending overload is invalid there.
• private builtin (--) Marks the next local created by NAME: ...; or def as non-public, so use does not import that name from the module.
• virtual builtin (--) Marks the next local created by NAME: ...; or def as static; virtual is the historical name for this declaration modifier.