assert.ts

export const assert = (condition: boolean, messageOrError?: string | Error) => {
  if (!condition) {
    if (typeof messageOrError === "string" || typeof messageOrError === "undefined") {
      const message = messageOrError || "Assertion failed";
      if (typeof Error !== "undefined") {
        throw new Error(message);
      }
    } else {
      throw messageOrError;
    }
  }
};

// pass specific error
// assert(url, new ValidationError("Required value missing: url"));

// or pass only message
// assert(url, "Required value missing: url");