Function operands

src/math-json/utils.ts:150–157

(
  expr: MathJsonExpression | null | undefined
)

 * or no arguments.
 */
export function operands(
  expr: MathJsonExpression | null | undefined
): ReadonlyArray<MathJsonExpression> {
  if (Array.isArray(expr)) return expr.slice(1) as MathJsonExpression[];
  if (expr !== undefined && isFunctionObject(expr)) return expr.fn.slice(1);

  return [];
}

/** Return the nth operand of a function expression */
export function operand(