callField (dict name -- fieldResult)

Inputs

• dict: Dict value or Ref to Dict used for field selection.
• name: Known Text field name used for selection.

Outputs

• fieldResult: Result produced by handling the selected field.

callField selects one Dict field by known Text name input and then applies the same field-handling semantics as .NAME.

Selection happens inside the builtin from the two data inputs.

Behavior

• The first input must dereference to Dict.
• The second input must be known Text at compile time.
• Matching candidates are tried from newest to oldest.
• A Block field is called.
• A Code field is called. Known NIL Code is invalid.
• A callable Dict field is selected with the same PRE and CALL rules as .NAME, then its CALL field is called.
• A non-static In-place field, including a non-callable Dict field, produces a new immutable Ref to the selected item, even when dict was reached mutably.
• A Ref field produces a copied Ref value.
• A Text field produces a copied Text value.
• A static or Meta field produces a new object from compile-time information instead of runtime field storage.
• The empty name "" selects unnamed fields and still follows the same newest-to-oldest candidate order.
• The empty Tuple () is invalid because the first input must dereference to Dict.
• Known Text locals are valid for name when their value is known at compile time.
• If no candidate matches, or if every matching callable Dict field fails its PRE test, the builtin raises a compilation error.

When the selected field is called, direct scope lookup inside that call matches .NAME: outer Dict fields are available, self is also available when dict was reached through a Ref, callable field Dict fields are available during PRE and CALL, closure is available for non-Meta non-static callable field Dict values, and direct-name conflicts during CALL favor the callable field Dict.

Example

{} 0 {} [
  dict: {
    outerValue: 7;
    number: 7;
    textField: "hi";
    metaField: ();
    blockField: [
      "-- block field --" printCompilerMessage
      self.outerValue printStack _:;
    ];
    choice: ["-- fallback --" printCompilerMessage];
    choice: {
      CALL: ["-- matched --" printCompilerMessage];
      PRE: ["-- PRE --" printCompilerMessage FALSE];
    };
  };
  numberName: "number";
  choiceName: "choice";

  "-- In-place field: callField versus .@NAME --" printCompilerMessage
  @dict numberName callField printStack _:;
  @dict .@number printStack _:;

  "-- text field --" printCompilerMessage
  @dict "textField" callField printStack _:;

  "-- meta field --" printCompilerMessage
  @dict "metaField" callField printStack _:;

  @dict "blockField" callField
  @dict choiceName callField

  0
] "main" exportFunction

Expected Output During Compilation

-- In-place field: callField versus .@NAME --
7 Cref
7 Ref
-- text field --
"hi"
-- meta field --
()
-- block field --
7 Cref
-- PRE --
-- fallback --

See also

• .@NAME node source form Named field read without calling.
• .NAME node source form Named field mention and call if callable.
• @ builtin (ordinal structValue -- selectedItem) Ordinal-based data-input selection and read with the ordinal before the Struct value. Callable items are read, not called.
• fieldRead builtin (structValue ordinal -- selectedItem) Ordinal-based data-input selection and read with the Struct value before the ordinal. Callable items are read, not called.