We have found the maintenance effort for programs written in Ada linear in the size of the code. It was a disaster. Poor performance, and we found we could not maintain the software. We are now rewriting it in procedurally oriented Ada at an estimated cost of 30 million dollars . The company I work for writes in the language the customer specifies.
All projects are of comparable size and complexity.
I have 3 people maintaining the Ada projects, and around 30 maintaining the ones in C. Company management is pushing for all new work to be done in C. Since the major thing we sell to our customer is engineering hours, and since we sell more hours for both development and and maintenance when we develop in C , the decision is a rational one to maximize our company's profits. Both students and instructors are randomly assigned, with each instructor teaching the same number of sections in each language each year. Our student evaluations consistently rate the instructors as better the times they teach Ada sections. After a period of experimentation, during which we taught some of our first class in programming sections in Pascal and some in Ada, we switched to Ada. Data we gathered while teaching both indicated no significant different in understanding, effort, or grades.