Function isNumberExpression

src/math-json/utils.ts:16–22

(
  expr: MathJsonExpression | null
)

export const MISSING: MathJsonExpression = ['Error', "'missing'"];

export function isNumberExpression(
  expr: MathJsonExpression | null
): expr is number | string | MathJsonNumberObject {
  if (typeof expr === 'number' || isNumberObject(expr)) return true;
  if (typeof expr === 'string' && matchesNumber(expr)) return true;
  return false;
}

export function isNumberObject(
  expr: MathJsonExpression | null