Documenting the history and roots of IMAGE has squirted out a stream of debate on the 3000 newsgroup. Terry O'Brien's project to make a TurboIMAGE Wikipedia page includes a reference to Fourth Generation Languages. His sentence below that noted 4GLs -- taken as fact by most of the 3000 community -- came in for a lively debate.
Several Fourth Generation Language products (Powerhouse, Transact, Speedware, Protos) became available from third party vendors.
While that seems innocent enough, retired 3000 manager Tom Lang has told the newsgroup there's no such thing as a Fourth Generation of any computer language. "My problem with so-called Fourth Generation Languages is the use of the term 'Language' attached to a commercial product," he wrote. The discussion has become a 59-message thread already, threatening to be the longest discussion on the newsgroup this year.
Although the question doesn't seem to merit debate, it's been like catnip to some very veteran developers who know MPE and the 3000. The 4GL term was probably cooked up by vendors' product managers and marketing experts. But such languages' value did exceed third generations like COBOL. The term has everything to do with advancing developer productivity, and the use of generations was an easy way to explain that benefit.
In fact, Cognos -- the biggest vendor of 4GLs in the 3000 world -- renamed its Powerhouse group the Advanced Development Tools unit, using ADT instead of 4GL. This was largely because of the extra value of a dictionary associated with Powerhouse. The dictionary was offered up as a distinction of a 4GL by Birket Foster. Then Stan Sieler, who's written a few compilers including SPLash!, a refreshed version of the 3000's SPL, weighed in with some essentials.
The list of the 3000's 4GLs is not a long one. HP dubbed Allbase as a 4GL at the same time that name signified a 3000 database alternative. It was a tool to develop more rapidly, HP said. Transact appears on some 4GL lists for MPE, but it's more often called a 3.5 GL, as is Protos. Not quite complete in their distinctions, although both have dictionaries. These languages all promised speed of development. They rose up in an era when object-oriented computing, with reusable elements, was mostly experimental.
Foster explained what made a 4GL an advanced tool.
The dictionary made the difference in these languages, allowing default formatting of fields, and enforcing rules on the data entry screens. I am a sure that a good Powerhouse or Speedware programmer can out-code a cut and paste COBOL programmer by about 10 to one. It also means that a junior team member is able to code business rules accurately, since the default edits/values come directly from the dictionary, ensuring consistency.
Sieler outlined what he believes makes up a language.
We all know what a 4GL is, to the extent that there’s a ’cloud’ / ’fuzzy shape’ labelled “4GL” in our minds that we can say “yes or no” for a given product, program, language, 4GL, package, or tarball. And we know that Speedware, etc., fit into that cloud.
Does a language have to have a published grammar? (Much less one published by an international standards organization?) Hell no! It’s better if it does, but that’s not only not necessary, but the grammar is missing and/or incomplete and/or inaccurate for many (probably most) computer languages, as well as almost all human languages (possibly excluding some post-priori languages). I speak as a compiler author of many decades (since about 1973).
Our SPLash! language (similar to HP’s SPL/V) had a BNF — at the start. (Indeed, we think we had the only accurate BNF for SPL/V.) But, as we added things to the language, they may or may not have been reflected in the BNF. We tried to update the manual, but may not have always been successful … if we got the change notice updated, I was happy.
Adding the word "product" behind 4GL seems to set things in perspective. O'Brien offered his summary of the 3000's rapid languages.
Speedware, Powerhouse, and Protos all had components (Powerhouse Quick, Speedware Reactor) that had a proprietary language syntax that offered Assignment, IO, and Conditional Logic. As such, they meet the minimum requirements to be referenced as a computer language. TurboIMAGE has a syntax for specifying the database schema, but does not have any component that meet the IO, Assignment, Conditional Logic, so it does not meet the minimum requirements.
Speedware and Powerhouse have had similar histories, both offered as ADT products. But the companies that control them have diverged in their missions. PowerHouse is now owned by Unicom Systems. Speedware's focus is now on legacy modernization services and tools, although its own 4GL is still a supported product.
There's an even more audacious tier of languages, one that the HP 3000 never saw. Fifth-generation languages, according to Wikipedia, "make the computer solve a given problem without the programmer. This way, the programmer only needs to worry about what problems need to be solved and what conditions need to be met, without worrying about how to implement a routine or algorithm to solve them." Prolog is one example of this fifth generation. But even Wikipedia's editors are wary of bringing forth a fifth generation.