Terry, Barry, and other non-rhyming posters, have provided good posts about various 4GLs.

I probably missed Tom’s initial post, or skipped it thinking it was unimportant, but from his later posts I get the feeling he won’t be happy unless some standards organization can produce some specs/grammar/etc that Speedware, or some other 4GL, matches.

So what?  Ignore him.  

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/tarball/whatever), 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 :)

Does a language have to be able to be converted to “machine language”?  Nope.  There’s this little concept called interpreters, plus P-Code from UCSD (where I roomed with one of the inventors :), plus the confusion as to what “machine language” even is!  

On most RS6000s, for example, no compiler emits machine language … because the true machine language is an IBM secret … each model implements an interpreter for what the compilers “think” is the machine language, an idea perhaps pioneered in the IBM 360 line.
  
On the Burroughs B1700, compilers emitted “machine code” for *different* machines (COBOL emitted code for one of two target machines, depending upon how many variables your code used; FORTRAN emitted code for a different “machine") … the underlying hardware (running picocode) multitasked running different microcode emulators for different apparent instruction sets, so *no* compiler ever emitted “machine code” :)  (Assuming you define “machine code” as instruction bits directly executed by the hardware.)

Stan

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