Function extractFieldValue

packages/compiler/src/typecheck/ops/signal_forms.ts:447–458

* Gets an expression that extracts the value of a field binding.

(expression: AST, tcb: Context, scope: Scope)

 * Gets an expression that extracts the value of a field binding.
 */
function extractFieldValue(expression: AST, tcb: Context, scope: Scope): TcbExpr {
  // Unwraps the field, e.g. `[field]="f"` turns into `f()`.
  const innerCall = new TcbExpr(tcbExpression(expression, tcb, scope).print() + '()');

  // Note: we ignore diagnostics on this call, because it might not be callable
  // (e.g. `undefined` is passed in). Whether the value conforms to `FieldTree` is
  // checked using the common inputs op.
  innerCall.markIgnoreDiagnostics();

  // Extract the value from the field, e.g. `f().value()`.
  return new TcbExpr(`${innerCall.print()}.value()`);
}

/**
 * Gets an expression that extracts the value signal of a field binding (without calling it).