C++ Beginner - 'error' as a command in code
<p>I am trying to work my way through a c++ textbook to learn some programming, but I've run into an issue with some of the sample code. The goal is to write a simple calculator program, and the text supplies parts of the code as examples. A portion is:</p>

<p>if (!cin) error("no second operand");</p>

<p>The text makes it seem like 'error' will the output the text that comes after it if your input is incorrect, but my compiler just says 'error' hasn't been defined. I'm copying the code from the text word for word, so I'm not sure if I'm missing something with my compiler, or if I've misunderstood how I should be writing the code. Can anyone give some advice?</p>
