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import {Binding, Expr, InitSignal, NewSignal} from 'vega-typings/types';
export interface Parameter {  /**   * Required. A unique name for the parameter. Parameter names should be valid JavaScript identifiers: they should contain only alphanumeric characters (or “$”, or “_”) and may not start with a digit. Reserved keywords that may not be used as parameter names are "datum", "event", "item", and "parent".   */  name: string;
  /**   * A text description of the parameter, useful for inline documentation.   */  description?: string;
  /**   * The initial value of the parameter.   *   * __Default value:__ `undefined`   */  value?: any;
  /**   * An expression for the value of the parameter. This expression may include other parameters, in which case the parameter will automatically update in response to upstream parameter changes.   */  expr?: Expr;
  /**   * Binds the parameter to an external input element such as a slider, selection list or radio button group.   */  bind?: Binding;}
export function assembleParameterSignals(params: Parameter[]) {  const signals: (NewSignal | InitSignal)[] = [];  for (const param of params || []) {    const {expr, bind, ...rest} = param;
    if (bind && expr) {      // Vega's InitSignal -- apply expr to "init"      const signal: InitSignal = {        ...rest,        bind,        init: expr      };      signals.push(signal);    } else {      const signal: NewSignal = {        ...rest,        ...(expr ? {update: expr} : {}),        ...(bind ? {bind} : {})      };      signals.push(signal);    }  }  return signals;}