• JohnZ <nospam myip.tks> Feb 28 2009
• "Tim M" <a b.com> Feb 28 2009
• Daniel Keep <daniel.keep.lists gmail.com> Feb 28 2009
• bearophile <bearophileHUGS lycos.com> Feb 28 2009
• Jarrett Billingsley <jarrett.billingsley gmail.com> Feb 28 2009
• JohnZ <not here.net> Mar 01 2009
• JohnZ <not here.net> Mar 01 2009
• johnZ <not here.net> Mar 01 2009
• Walter Bright <newshound1 digitalmars.com> Feb 28 2009
• JohnZ <not here.net> Mar 01 2009

JohnZ <nospam myip.tks> writes:

In this case what would be the pros and cons if any of D compared with
C or asm?

"Tim M" <a b.com> writes:

On Sat, 28 Feb 2009 22:53:25 +1300, JohnZ <nospam myip.tks> wrote:

 In this case what would be the pros and cons if any of D compared with
 C or asm?



C probably optimizes well based on its age. Asm will make some routines a  
few microseconds faster. But D will ensure whole project not be delayed by  
a few years.

Profile the d for the slow spots, optimize those and maybe include inline  
asm there. Have the ability to link to existing c (and some C++) libraries  
if needed. Profit :)

D is well suited to interpreters.

PS: any thing unique about forth interpreters compared to other  
interpreted languages?

Daniel Keep <daniel.keep.lists gmail.com> writes:

Tim M wrote:
 PS: any thing unique about forth interpreters compared to other
 interpreted languages?


Forth (actually, postfix languages in general) are awesome fun, and
they're incredibly simple to play with.  I made a simple Forth-like
language interpreter in Python to play around with the idea of a
postscript-style language for cairo rendering.

I managed to get it to the point where if and subroutines were
implemented as functions, which I thought was just hilarious.  :D

  -- Daniel


P.S.  Here's an old fib subroutine I made in it.  Anything in ( parens )
is a comment.


( Defines a fib word that computes the nth Fibonacci number. )

`fib ( n -- n' ) :
    dup 1 <= not
    if-then
        1-
        dup
             fib
        swap 1- fib
        +
    end-if
    .

bearophile <bearophileHUGS lycos.com> writes:

JohnZ Wrote:
In this case what would be the pros and cons if any of D compared with C or
asm?<


If you use C with GCC you can use the computed goto, that is really useful to
speed up an interpreter like a Forth one. D misses still such feature because
it was thought as not useful enough.

Bye,
bearophile

Jarrett Billingsley <jarrett.billingsley gmail.com> writes:

On Sat, Feb 28, 2009 at 6:10 AM, bearophile <bearophileHUGS lycos.com> wrote:
 JohnZ Wrote:
In this case what would be the pros and cons if any of D compared with C or
asm?<


 If you use C with GCC you can use the computed goto, that is really useful to
speed up an interpreter like a Forth one. D misses still such feature because
it was thought as not useful enough.


D turns many switch statements into computed gotos.  It's a compiler
optimization.

JohnZ <not here.net> writes:

== Quote from Jarrett Billingsley (jarrett.billingsley gmail.com)'s
article
 On Sat, Feb 28, 2009 at 6:10 AM, bearophile


 JohnZ Wrote:
In this case what would be the pros and cons if any of D compared






 If you use C with GCC you can use the computed goto, that is




still such feature because it was thought as not useful enough.
 D turns many switch statements into computed gotos.  It's a compiler
 optimization.


ah that might be useful..

JohnZ <not here.net> writes:

== Quote from bearophile (bearophileHUGS lycos.com)'s article
 JohnZ Wrote:
In this case what would be the pros and cons if any of D compared




 If you use C with GCC you can use the computed goto, that is really


such feature because it was thought as not useful enough.
 Bye,
 bearophile


ah....project similar to forth interpreter was an easy way of saying
an attempt at an interaction machine emulator. if any of you know who
Peter Wegner is you'll get the joke here :D

johnZ <not here.net> writes:

sorry I emailed you...twice..first time I clicked reply to author by
accident..

JohnZ

Walter Bright <newshound1 digitalmars.com> writes:

JohnZ wrote:
 In this case what would be the pros and cons if any of D compared with
 C or asm?


You can compare C++ for an interpreter with the same code translated to 
D with Digital Mars' javascript engine 
http://www.digitalmars.com/dscript/index.html

The D version is about 30% less source code and runs slightly faster.

JohnZ <not here.net> writes:

 You can compare C++ for an interpreter with the same code translated


 D with Digital Mars' javascript engine
 http://www.digitalmars.com/dscript/index.html
 The D version is about 30% less source code and runs slightly faster.


Thanks I'll take a look at the source code