Alternatives to C: ObjectPascal, Eiffel, Ada or Modula-3?
in [ADA]
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From: Adam Beneschan on 24 Mar 2010 17:36 On Mar 24, 8:07 am, Warren <ve3...(a)gmail.com> wrote: > >> > IOW, stay away from the likes of Java, C#, Pascal. Unless you > >> > have a > >> > very specific reason for going in that direction. Your performance > >> > will suffer. > >> > Jim > > >> I don't think many people would be surprised by these results. > >> After all Java, C# and Pascal (variants) are still largely > >> interpreted languages, even if they use some sort of compiled > >> intermediate code. > > > Pascal is not an interpreted language. One of Pascal's selling points > > was that it was one of the first languages that could be parsed by a > > simple recursive descent parser without backtracking. > > P-code implementations were. So all this means is that if we compared the performance of a C compiler with the performance of a p-code implementation of Pascal, we shouldn't be surprised if the Pascal program runs slower. That's pretty obvious, and also pretty pointless. Users who are concerned about performance would want to compare a C compiler with a Pascal compiler that generates native code. Those Pascal compilers are readily available, and there's no inherent reason why they would show worse performance than C code (if you turn off range checking), since Pascal is not an interpreted language (as opposed to, say, Lisp or Perl, which *are* interpreted languages and which would normally not get you anywhere near the performance of a C program). -- Adam
From: Adam Beneschan on 24 Mar 2010 18:14 On Mar 24, 2:27 pm, p...(a)informatimago.com (Pascal J. Bourguignon) wrote: > > True. But P-code was for student use, not production, especially not > > production in an application where execution time was critical. > > This is wrong. > > P-code was designed, and used, exactly like the JVM is today. There > even were developed processors that executed directly P-code, natively, > like we have JVM implemented in hardware too. I think Patrick is essentially correct; the Wikipedia entry for "UCSD Pascal" says: "The University of California, San Diego Institute for Information Systems developed it in 1978 to provide students with a common operating system that could run on any of the then available microcomputers as well as campus DEC PDP-11 minicomputers." [This was before the IBM PC came out, so I think "then available microcomputers" meant Terak and maybe Apple II; perhaps there were some others.] So, yes, it was originally designed for student use; I don't believe the original designers had any commercial use in mind. But its use spread after that. -- Adam
From: Patrick Scheible on 24 Mar 2010 19:15 Adam Beneschan <adam(a)irvine.com> writes: > On Mar 24, 2:27=A0pm, p...(a)informatimago.com (Pascal J. Bourguignon) > wrote: > > > > True. =A0But P-code was for student use, not production, especially not > > > production in an application where execution time was critical. > > > > This is wrong. > > > > P-code was designed, and used, exactly like the JVM is today. =A0There > > even were developed processors that executed directly P-code, natively, > > like we have JVM implemented in hardware too. > > I think Patrick is essentially correct; the Wikipedia entry for "UCSD > Pascal" says: > > "The University of California, San Diego Institute for Information > Systems developed it in 1978 to provide students with a common > operating system that could run on any of the then available > microcomputers as well as campus DEC PDP-11 minicomputers." [This was > before the IBM PC came out, so I think "then available microcomputers" > meant Terak and maybe Apple II; perhaps there were some others.] I encountered it on a CP/M system. S-100 bus, Z80 processor. Apple II's that I saw didn't run it, but I wouldn't swear that it was impossible. -- Patrick
From: Adam Beneschan on 24 Mar 2010 19:24 On Mar 24, 4:15 pm, Patrick Scheible <k...(a)zipcon.net> wrote: > I encountered it on a CP/M system. S-100 bus, Z80 processor. Apple > II's that I saw didn't run it, but I wouldn't swear that it was > impossible. I recall doing some work with UCSD Pascal on an Apple II (probably II +) at UC Irvine. -- Adam
From: Patricia Shanahan on 24 Mar 2010 19:28
Patrick Scheible wrote: > Adam Beneschan <adam(a)irvine.com> writes: > >> On Mar 24, 2:27=A0pm, p...(a)informatimago.com (Pascal J. Bourguignon) >> wrote: >> >>>> True. =A0But P-code was for student use, not production, especially not >>>> production in an application where execution time was critical. >>> This is wrong. >>> >>> P-code was designed, and used, exactly like the JVM is today. =A0There >>> even were developed processors that executed directly P-code, natively, >>> like we have JVM implemented in hardware too. >> I think Patrick is essentially correct; the Wikipedia entry for "UCSD >> Pascal" says: >> >> "The University of California, San Diego Institute for Information >> Systems developed it in 1978 to provide students with a common >> operating system that could run on any of the then available >> microcomputers as well as campus DEC PDP-11 minicomputers." [This was >> before the IBM PC came out, so I think "then available microcomputers" >> meant Terak and maybe Apple II; perhaps there were some others.] > > I encountered it on a CP/M system. S-100 bus, Z80 processor. Apple > II's that I saw didn't run it, but I wouldn't swear that it was > impossible. Apple Pascal was based on UCSD Pascal. I ran it frequently on my Apple II. According to the reference manual, it required 48 KB memory, at least one Apple II disk drive, and the Apple Language System. Patricia |