Alan Perlis Quotes

In the computer field, the moment of truth is a running program; all else is prophecy.

There are two methods in software design. One is to make the program so simple, there are obviously no errors. The other is to make it so complicated, there are no obvious errors.

Running the test suite like this allows us to catch problems when they are just introduced.

One of my most productive days was throwing away 1,000 lines of code.

Writing software is a very intense, very personal thing. You have to have time to work your way through it, to understand it. Then debug it.

The fundamental problem with program maintenance is that fixing a defect has a substantial chance of introducing another.

I'm not saying we purposely introduced bugs or anything, but this is kind of a natural result of any complexities of software... that you can't fully test it.

The problem is, in software design, often the consequences of your decisions don't become apparent for years.

The critical thing in developing software is not the program, it's the design. It is translating understanding of user needs into something that can be realized as a computer program.

I found out that most programmers don't like to test their software as intensely as I do.

Most of the effort in the software business goes into the maintenance of code that already exists.

I used Agitator on some code I had unit-tested, and it made me a better tester. As an Agitar Fellow, I look forward to the leverage of working with an outstanding organization as together we continue to improve the value of developer testing.

I had to actually purchase a book to learn the API and write the client. It was pretty frustrating trying to learn the API and develop a product quickly.

There has never been an unexpectedly short debugging period in the history of computers.

When you say 'I wrote a program that crashed Windows,' people just stare at you blankly and say 'Hey, I got those with the system, for free.'

My list of basic tools is a partial answer to the question about what has changed: Over the past few years, large numbers of programmers have come to depend on elaborate tools to interface code with systems facilities.

Cosmoe is nearing the stage where I would feel comfortable doing a preliminary release aimed at developers.

So Chuck and I looked at that and we hacked on em for a while, and eventually we ripped the stuff out of em and put some of it into what was then called en, which was really ed with some em features.

No matter what, the way to learn to program is to write code and rewrite it and see it used and rewrite again. Reading other people's code is invaluable as well.

An individual developer like me cares about writing the new code and making it as interesting and efficient as possible. But very few people want to do the testing.

I had almost rewritten all of the display code for windows, and that was when I gave up.

Developer testing is an important step towards accountability. It gives developers a way to demonstrate the quality of the software they produce.

The mark of a mature programmer is willingness to throw out code you spent time on when you realize it's pointless.

In the practical world of computing, it is rather uncommon that a program, once it performs correctly and satisfactorily, remains unchanged forever.

But active programming consists of the design of new programs, rather than contemplation of old programs.