function form_verficiation_error_message(type?: string, field?: string) {
   let msg = "Parameter verification failed! ";
   if (type && field) {
      msg += `At ${type}.${field}! `;
   } else if (type) {
      msg += `At type ${type}! `;
   } else if (field) {
      msg += `At field ${field}! `;
   }
   return msg;
}

export class VerificationError extends Error {
   constructor(
      public readonly type?: string,
      public readonly field?: string,
      public readonly value?: any
   ) {
      super(form_verficiation_error_message(type, field));
   }
}

export function apply_int(data: any) {
   data = Math.floor(Number(data));
   if (Number.isNaN(data)) throw new VerificationError("int", undefined, data);
   return data;
}

export function apply_float(data: any) {
   data = Number(data);
   if (Number.isNaN(data))
      throw new VerificationError("float", undefined, data);
   return data;
}

export function apply_string(data: any) {
   return String(data);
}

export function apply_boolean(data: any) {
   return Boolean(data);
}

export function apply_void(data: any) { }