Error Reporting with Graduated Color

A technique for nonintrusive error notification during programming that uses graduated color and elision, the temporary hiding of information, is described. Users can see errors and their age by the color and can look at the associated error explanation when they are not busy. Interruption is kept to a minimum during notification, and the explanation is close at hand and complete when it is wanted. The application of this technique to the Cornell synthesizer Generator is discussed, and sample generated displays are presented.