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Groups > comp.lang.java.programmer > #32707
| From | Martin Gregorie <martin@address-in-sig.invalid> |
|---|---|
| Newsgroups | comp.lang.java.programmer |
| Subject | Re: questions re Javascript |
| Date | 2015-09-25 19:59 +0000 |
| Organization | A noiseless patient Spider |
| Message-ID | <mu493n$4ur$1@dont-email.me> (permalink) |
| References | (7 earlier) <mu25v8$6dd$1@dont-email.me> <mu3afq$sn3$1@dont-email.me> <mu3b4k$anl$1@dont-email.me> <mu3uiu$fq4$1@dont-email.me> <mu42a2$8rl$1@dont-email.me> |
On Fri, 25 Sep 2015 14:03:55 -0400, Jeff Higgins wrote:
> On 09/25/2015 01:00 PM, Martin Gregorie wrote:
>> On Fri, 25 Sep 2015 12:30:22 +0100, Eternal Hope wrote:
>>
>>> On 25/09/2015 12:17, Martin Gregorie wrote:
>>>> On Thu, 24 Sep 2015 20:55:59 -0400, Jerry Stuckle wrote:
>>>>
>>>>> Again - let's see you build the hardware. Then maybe we can discuss
>>>>> it.
>>>>>
>>>> Its already been done. https://en.wikipedia.org/wiki/Java_processor
>>>>
>>>> Or, just find a Jazelle chip or Javelin device and use that. Parallax
>>>> sold the Javelin. Physically they were very similar to their BS2
>>>> STAMP.
>>>> However, they did that quite a while back, so it will be Java 1 or 2
>>>> at the most.
>>>>
>>>> There's an interesting discussion in this reference: http://
>>>> www.jopdesign.com/doc/jhal.pdf I just skimmed it, but it looks as
>>>> though they've had at least one HW implementation running.
>>>>
>>>> In any case, what does seeing a hardware implementation have to do
>>>> with a thread about clarifying natural language definitions and their
>>>> associated semantics?
>>>
>>> Splutter !!!
>>>
>>> You bought it up in the first place Martin. and you haven't yet
>>> answered the quastion about how your byte code gets translated into
>>> binary numbers ... how does that happen ?
>>>
>> How do you work that out? I did explicitly NOT make a distinction
>> between bytecode compilers and machine code compilers: indeed GCJ can
>> generate both. Pretty much at the start of all this, I said two things:
>>
>> 1) that you can define a high-level 'compiled language' as one where
>> a program, usually known as a 'compiler', must be used to translate
>> the human readable source code into something more computer
>> friendly before it can be run and that an interpreted language does
>> not have an explicit compilation step.
>>
>> 2) that compilers or assemblers that can directly generate executable
>> code without the aid of a linker are rare in my experience and that
>> I knew three cases (6800 assemblers, PL/9 and Elliott 503 Algol) of
>> compiled languages that don't use a linker in the sense of a
>> post-processor for compiler output.
>>
>> I should have included Java in this list since it too lacks an
>> explicit linkage stage that must be completed before attempting to
>> run the compiled code: my mistake. I suppose any system that can
>> run relocatable binary code can let the runtime loader handle
>> fixing up inter-module links. The JVM's loader does this and IIRC
>> so do the loaders used by IBM's OS/400 and ICL's VME/B
>>
>> I have always heard the phrase 'interpreted languages' used to describe
>> the case where source code is apparently executed directly without any
>> explicit compilation stage. Examples are Perl, awk and command-line
>> interpreters, e.g. bash or command.exe
>>
>>
> There are a dozen or so products described by their suppliers as C
> interpreters. Does this mean that C is an interpreted language?
>
The common C versions (K&R C, ANSI C and its derivative, C++) are
definitely compiled languages using a complex, multi-phase compiler.
'cc' itself is just a shell to run the appropriate compilation phases in
the required order:
- preprocessor (a macrogenerator: it expands macro definitions,
and #defines, uses #ifdef statements to control what
parts of the source files are fed to the compiler
- assembly language generator (translates C source to the native
assembler)
- optimiser (applies the requested optimisations (inlining code,
unrolling loops etc)
- assembler
- linker
How much of this you're aware of during a compilation depends on the
actual compiler. For instance:
- GNU C looks and acts like a single unitary slab most of the time
- Microware K&R C compiler for OS-9 showed all the phases as they
were run.
- most Unices, which include Linux and BSD, also have the 'ar' tool,
which is used to build code libraries, and 'make', which does much
the same job as 'ant'.
Other OSen have equivalent tools.
However, there is an interpreted language, Tiny C, which is purely
interpreted. It dates from the time when an Intel 8080 was considered a
desirable mpu. Tiny C was really an IDE, being a combined
editor,compiler,interpreter - in short, very similar to a traditional
BASIC.
Tiny C claimed to be a very small (integer) subset of C, but in fact
doesn't look a lot like it. Here's 'hello World' in tiny C:
hello-world [
pl "Hello, world"
]
and here's the equivalent in ANSI C:
/* HELLO.C - compiler test piece */
#include <stdio.h>
int main(int argc, char **argv)
{
printf("Hello, C world\n");
return(0);
}
> That these products are not really C language products?
>
Does Tiny C look anything like the product you were thinking of?
> That somehow behind the scenes these products are really C
> language compilers masquerading as C interpreters?
>
I would say not, though of course people can and do use Eclipse for C
development, which would make it all look a lot different from the way I
develop C. But then, I develop C using a traditional multi-buffered
editor (microEmacs) plus make, GNU C ar and cvs for version control. I
run the lot from two or three console windows and command lines.
> Something else? Does it make sense to
> declare a language as only either a compiled language or an interpreted
> language?
>
I think mostly yes, if only because interpreted languages tend to be much
terser and use untyped variables both of which make them easier and
quicker to enter and edit.
> Are there any programming languages that one strictly cannot
> compile or interpret?
>
Don't know. Strongly typed languages may be a pain to interpret line by
line as they're entered (think JOSS or Forth here) simply because you'll
probably have to enter the whole program and enter 'RUN' before type
mismatches etc get found and reported.
I have a feeling that the ones that claim to be both will be organised
rather like traditional BASIC or Python, i.e. a combination of editor/IDE,
P-code compiler and interpreter. If you run these in interactive mode
they just a source editor until you enter the RUN command to cause a
compile-and-go. If the compile is successful, the program is run and
after it ends or fails you're back in the editor. If you run it as a
command (basic myprog.bas) then it will read in the file, do a command-
and-go and return errors and/or results to the console.
> Somehow it makes more sense to me to say that a
> particular programming language is usually compiled to some form of
> native machine language, or is more usually interpreted by some virtual
> machine running on a native machine. I'm by far no C expert but I do
> seem to recall a C standard somehow referring to a virtual machine.
>
Agreed. Those that work both ways are fairly rare, especially if they
aren't IDE-like. Sorry to keep dragging up old systems, but about the
only ones, apart from various BASICs and JOSS, that worked this way that
I know about were the command processors for ICL's VME/B and IBM's
OS/400 operating systems. Both worked similarly and both used strongly
typed command languages, so error detection was excellent:
- If you typed in a command it ran it and prompted for another
- if you entered the command name and hit a special key, you got a
fullscreen prompt showing command names and boxes alongside each to
fill in. Default values were shown and could be overtyped.
Hitting ENTER ran the completed command.
- if you started an editor and used it to write a command script,
you set up a header with argument names, types and defaults, typed
in the commands, loops and conditionals etc and closed the file.
Under OS/400 you compiled it by running CRTCLPGM and fixed errors
like any other program before you could run your new command.
CRTCLPGM looks horrid but is a shortened form of "Create Command
Language Program" but is easier to remember than you'd expect. Yes,
CRTCPGM was the C compiler and CRTPLIPGM was the PL/I compiler.
Under VME/B you simply issued the filename as a command, which tried
a compile-and-go. If it compiled, it would run. If not, you fixed
errors and tried again.
Under both OS/400 and VME/B your new command worked just like a built-in
one: you could run it from a command line, cause it to do a full screen
prompt for arguments, or call it from another command file.
--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |
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questions re Javascript rdelaney2001@gmail.com - 2015-09-01 15:26 -0700
Re: questions re Javascript Martin Gregorie <martin@address-in-sig.invalid> - 2015-09-01 23:26 +0000
Re: questions re Javascript Eternal Hope <laughingspam99@gmail.com> - 2015-09-02 10:00 +0100
Re: questions re Javascript e.d.programmer@gmail.com - 2015-09-02 05:32 -0700
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-09-03 20:17 -0400
Re: questions re Javascript e.d.programmer@gmail.com - 2015-09-04 05:33 -0700
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-10-05 22:42 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-09-01 20:00 -0400
Re: questions re Javascript Eternal Hope <laughingspam99@gmail.com> - 2015-09-05 20:40 +0100
Re: questions re Javascript Lew <lewbloch@gmail.com> - 2015-09-23 16:10 -0700
Re: questions re Javascript Eternal Hope <laughingspam99@gmail.com> - 2015-09-24 10:40 +0100
Re: questions re Javascript Martin Gregorie <martin@address-in-sig.invalid> - 2015-09-24 11:21 +0000
Re: questions re Javascript Eternal Hope <laughingspam99@gmail.com> - 2015-09-24 20:10 +0100
Re: questions re Javascript Lew <lewbloch@gmail.com> - 2015-09-24 13:18 -0700
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-24 19:40 -0400
Re: questions re Javascript Martin Gregorie <martin@address-in-sig.invalid> - 2015-09-25 01:15 +0000
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-24 22:25 -0400
Re: questions re Javascript Eternal Hope <laughingspam99@gmail.com> - 2015-09-25 03:46 +0100
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-25 09:59 -0400
Re: questions re Javascript Eternal Hope <laughingspam99@gmail.com> - 2015-09-25 15:32 +0100
Re: questions re Javascript Lew <lewbloch@gmail.com> - 2015-10-02 13:02 -0700
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-10-02 16:24 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-10-02 23:02 -0400
Re: questions re Javascript Eternal Hope <laughingspam99@gmail.com> - 2015-10-03 13:30 +0100
Re: questions re Javascript Lew <lewbloch@gmail.com> - 2015-10-04 21:31 -0700
Re: questions re Javascript Eternal Hope <laughingspam99@gmail.com> - 2015-10-05 07:48 +0100
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-10-05 20:53 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-10-03 10:46 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-10-05 21:00 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-10-05 21:19 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-10-05 22:26 -0400
Re: questions re Javascript Eternal Hope <laughingspam99@gmail.com> - 2015-09-25 15:32 +0100
Re: questions re Javascript Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-09-24 16:58 -0400
Re: questions re Javascript Martin Gregorie <martin@address-in-sig.invalid> - 2015-09-24 21:45 +0000
Re: questions re Javascript Jeff Higgins <jeff@invalid.invalid> - 2015-09-24 18:27 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-24 19:53 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-09-24 22:03 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-24 22:34 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-09-24 22:46 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-25 09:56 -0400
Re: questions re Javascript Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-09-25 10:15 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-25 11:44 -0400
Re: questions re Javascript Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-09-25 14:09 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-25 15:15 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-09-27 20:45 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-27 22:48 -0400
Re: questions re Javascript Martin Gregorie <martin@address-in-sig.invalid> - 2015-09-28 03:29 +0000
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-28 00:02 -0400
Re: questions re Javascript Martin Gregorie <martin@address-in-sig.invalid> - 2015-09-28 11:33 +0000
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-28 10:44 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-09-27 20:42 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-27 22:51 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-09-27 20:38 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-27 22:59 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-10-02 22:47 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-10-03 10:48 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-10-02 22:53 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-10-03 10:52 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-10-05 21:03 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-10-05 21:25 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-10-05 21:41 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-10-05 22:11 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-10-05 22:19 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-10-05 22:27 -0400
Re: questions re Javascript Jeff Higgins <jeff@invalid.invalid> - 2015-09-24 22:30 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-24 22:42 -0400
Re: Aho, A. V., & Ullman, J. D. (1972). The theory of parsing, translation, and compiling. Englewood Cliffs, N.J: Prentice-Hall. Jeff Higgins <jeff@invalid.invalid> - 2015-09-24 23:26 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-09-24 23:07 -0400
Re: questions re Javascript Jeff Higgins <jeff@invalid.invalid> - 2015-09-24 23:55 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-09-27 20:46 -0400
Re: questions re Javascript e.d.programmer@gmail.com - 2015-09-25 05:20 -0700
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-09-27 20:54 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-27 23:05 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-10-02 22:36 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-10-03 10:57 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-10-05 21:10 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-10-05 21:27 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-27 23:19 -0400
Re: questions re Javascript Eternal Hope <laughingspam99@gmail.com> - 2015-09-25 03:46 +0100
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-09-24 23:35 -0400
Re: questions re Javascript Lew <lewbloch@gmail.com> - 2015-09-24 13:10 -0700
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-24 19:55 -0400
Re: questions re Javascript Martin Gregorie <martin@address-in-sig.invalid> - 2015-09-25 00:48 +0000
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-24 20:55 -0400
Re: questions re Javascript Martin Gregorie <martin@address-in-sig.invalid> - 2015-09-25 11:17 +0000
Re: questions re Javascript Eternal Hope <laughingspam99@gmail.com> - 2015-09-25 12:30 +0100
Re: questions re Javascript Martin Gregorie <martin@address-in-sig.invalid> - 2015-09-25 17:00 +0000
Re: questions re Javascript Jeff Higgins <jeff@invalid.invalid> - 2015-09-25 14:03 -0400
Re: questions re Javascript Jeff Higgins <jeff@invalid.invalid> - 2015-09-25 14:14 -0400
Re: questions re Javascript Martin Gregorie <martin@address-in-sig.invalid> - 2015-09-25 19:59 +0000
Re: questions re Javascript Jeff Higgins <jeff@invalid.invalid> - 2015-09-25 17:13 -0400
Re: questions re Javascript Martin Gregorie <martin@address-in-sig.invalid> - 2015-09-25 22:15 +0000
Re: questions re Javascript Lew <lewbloch@gmail.com> - 2015-10-02 13:07 -0700
Re: questions re Javascript Eternal Hope <laughingspam99@gmail.com> - 2015-10-03 16:48 +0100
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-25 10:02 -0400
Re: questions re Javascript Martin Gregorie <martin@address-in-sig.invalid> - 2015-09-25 17:32 +0000
Re: questions re Javascript Eternal Hope <laughingspam99@gmail.com> - 2015-09-25 03:45 +0100
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-25 10:13 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-09-24 21:58 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-09-24 22:34 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-24 22:35 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-09-24 22:51 -0400
Re: questions re Javascript Arne Vajhøj <arne@vajhoej.dk> - 2015-09-24 23:00 -0400
Re: questions re Javascript Jerry Stuckle <jstucklex@attglobal.net> - 2015-09-25 10:17 -0400
Re: questions re Javascript Tim Slattery <tim@risingdove.com> - 2015-09-24 12:04 -0400
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