Influential programming languages: some of the considerations

Derek Jones from The Shape of Code

Which programming languages have been the most influential?

Let’s define an influential language as one that has had an impact on lots of developers. What impact might a programming language have on developers?

To have an impact a language needs to be used by lots of people, or at least have a big impact on a language that is used by lots of people.

Figuring out the possible impacts a language might have had is very difficult, requiring knowledge of different application domains, software history, and implementation techniques. The following discussion of specific languages illustrate some of the issues.

Simula is an example of a language used by a handful of people, but a few of the people under its influence went on to create Smalltalk and C++. Some people reacted against the complexity of Algol 68, creating much simpler languages (e.g., Pascal), while others thought some of its feature were neat and reused them (e.g., Bourne shell).

Cobol has been very influential, at least within business computing (those who have not worked in business computing complain about constructs handling uses that it was not really designed to handle, rather than appreciating its strengths in doing what it was designed to do, e.g., reading/writing and converting a wide range of different numeric data formats). RPG may have been even more influential in this usage domain (all businesses have to specific requirements on formatting reports).

I suspect that most people could not point to the major influence C has had on almost every language since. No, not the use of { and }; if a single character is going to be used as a compound statement bracketing token, this pair are the only available choice. Almost every language now essentially uses C’s operator precedence (rather than Fortran‘s, which is slightly different; R follows Fortran).

Algol 60 has been very influential: until C came along it was the base template for many languages.

Fortran is still widely used in scientific and engineering software. Its impact on other languages may be unknown to those involved. The intricacies of floating-point arithmetic are difficult to get right, and WG5 (the ISO language committee, although the original work was done by the ANSI committee, J3). Fortran code is often computationally intensive, and many optimization techniques started out optimizing Fortran (see “Optimizing Compilers for Modern Architectures” by Allen and Kennedy).

BASIC showed how it was possible to create a usable interactive language system. The compactness of its many, and varied, implementations were successful because they did not take up much storage and were immediately usable.

Forth has been influential in the embedded systems domain, and also people fall in love with threaded code as an implementation technique (see “Threaded Interpretive Languages” by Loeliger).

During the mid-1990s the growth of the Internet enabled a few new languages to become widely used, e.g., PHP and Javascript. It’s difficult to say whether these were more influenced by what their creators ate the night before or earlier languages. PHP and Javascript are widely used, and they have influenced the creation of many languages designed to fix their myriad of issues.

First language taught to undergraduates in the 1990s

Derek Jones from The Shape of Code

The average new graduate is likely to do more programming during the first month of a software engineering job, than they did during a year as an undergraduate. Programming courses for undergraduates is really about filtering out those who cannot code.

Long, long ago, when I had some connection to undergraduate hiring, around 70-80% of those interviewed for a programming job could not write a simple 10-20 line program; I’m told that this is still true today. Fluency in any language (computer or human) takes practice, and the typical undergraduate gets very little practice (there is no reason why they should, there are lots of activities on offer to students and programming fluency is not needed to get a degree).

There is lots of academic discussion around which language students should learn first, and what languages they should be exposed to. I have always been baffled by the idea that there was much to be gained by spending time teaching students multiple languages, when most of them barely grasp the primary course language. When I was at school the idea behind the trendy new maths curriculum was to teach concepts, rather than rote learning (such as algebra; yes, rote learning of the rules of algebra); the concept of number-base was considered to be a worthwhile concept and us kids were taught this concept by having the class convert values back and forth, such as base-10 numbers to base-5 (base-2 was rarely used in examples). Those of us who were good at maths instantly figured it out, while everybody else was completely confused (including some teachers).

My view is that there is no major teaching/learning impact on the choice of first language; it is all about academic fashion and marketing to students. Those who have the ability to program will just pick it up, and everybody else will flounder and do their best to stay away from it.

Richard Reid was interested in knowing which languages were being used to teach introductory programming to computer science and information systems majors. Starting in 1992, he contacted universities roughly twice a year, asking about the language(s) used to teach introductory programming. The Reid list (as it became known), was regularly updated until Reid retired in 1999 (the average number of universities included in the list was over 400); one of Reid’s ex-students, Frances VanScoy, took over until 2006.

The plot below is from 1992 to 2002, and shows languages in the top 3% in any year (code+data):

Normalised returned required for various elapsed years.

Looking at the list again reminded me how widespread Pascal was as a teaching language. Modula-2 was the language that Niklaus Wirth designed as the successor of Pascal, and Ada was intended to be the grown up Pascal.

While there is plenty of discussion about which language to teach first, doing this teaching is a low status activity (there is more fun to be had with the material taught to the final year students). One consequence is lack of any real incentive for spending time changing the course (e.g., using a new language). The Open University continued teaching Pascal for years, because material had been printed and had to be used up.

C++ took a while to take-off because of its association with C (which was very out of fashion in academia), and Java was still too new to risk exposing to impressionable first-years.

A count of the total number of languages listed, between 1992 and 2002, contains a few that might not be familiar to readers.

          Ada    Ada/Pascal          Beta          Blue             C 
         1087             1            10             3           667 
       C/Java      C/Scheme           C++    C++/Pascal        Eiffel 
            1             1           910             1            29 
      Fortran       Haskell     HyperTalk         ISETL       ISETL/C 
          133            12             2            30             1 
         Java  Java/Haskell       Miranda            ML       ML/Java 
          107             1            48            16             1 
     Modula-2      Modula-3        Oberon      Oberon-2     ObjPascal 
          727            24            26             7            22 
       Orwell        Pascal      Pascal/C        Prolog        Scheme 
           12          2269             1            12           752 
    Scheme/ML Scheme/Turing        Simula     Smalltalk           SML 
            1             1            14            33            88 
       Turing  Visual-Basic 
           71             3 

I had never heard of Orwell, a vanity language foisted on Oxford Mathematics and Computation students. It used to be common for someone in computing departments to foist their vanity language on students; it enabled them to claim the language was being used and stoked their ego. Is there some law that enables students to sue for damages?

The 1990s was still in the shadow of the 1980s fashion for functional programming (which came back into fashion a few years ago). Miranda was an attempt to commercialize a functional language compiler, with Haskell being an open source reaction.

I was surprised that Turing was so widely taught. More to do with the stature of where it came from (university of Toronto), than anything else.

Fortran was my first language, and is still widely used where high performance floating-point is required.

ISETL is a very interesting language from the 1960s that never really attracted much attention outside of New York. I suspect that Blue is BlueJ, a Java IDE targeting novices.