Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.forth > #27864

Re: late binding

Show all headers | View raw

Paul Rubin <no.email@nospam.invalid> writes:
> You can
>redefine BAR:
>
>   : FOO 1 BAR + ;
>   : BAR 4 ;
>
>   FOO   5 ok    \ FOO prints 5
>
>   : BAR 8 ;     \ overwrite the same CFA again
>   FOO   9 ok    \ FOO now prints 9
>
>It costs an extra memory access depending on implementation, not too
>bad.  The advantage is you can now redefine words during debugging,
>without having to reload the whole program which usually means
>clobbering the program state.  When you redefine a word, all callers
>will now call the new word.  Also you no longer have to define each word
>before it's used.
>
>I know you can do a version of this with DEFER, but this idea is more
>pervasive.
>
>Is this just terrible, from a Forth cultural (or other) standpoint?

At least it's not as terrible as EVALUATE-based macros, because this
kind of redefinition binds at the compile time of the new BAR, whereas
EVALUATE-based macros are a gross cross between early and late
binding; and yet, EVALUATE-based macros have their fans, so your
simulation of late binding will probably be acceptable to many.

Anyway, the standard Forth way of name binding works out very well for
dealing with multiple independent definitions of the same name (see
<http://www.complang.tuwien.ac.at/forth/language-features.html>; I
should expand the other sections:-).

- anton
-- 
M. Anton Ertl  http://www.complang.tuwien.ac.at/anton/home.html
comp.lang.forth FAQs: http://www.complang.tuwien.ac.at/forth/faq/toc.html
     New standard: http://www.forth200x.org/forth200x.html
   EuroForth 2013: http://www.euroforth.org/ef13/

Back to comp.lang.forth | Previous | Next — Previous in thread | Find similar | Unroll thread

Thread

late binding Paul Rubin <no.email@nospam.invalid> - 2014-01-11 01:59 -0800
  Re: late binding Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-01-11 04:16 -0600
    Re: late binding Paul Rubin <no.email@nospam.invalid> - 2014-01-11 03:06 -0800
      Re: late binding anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-01-13 15:31 +0000
  Re: late binding albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-01-11 14:05 +0000
  Re: late binding Ron Aaron <rambamist@gmail.com> - 2014-01-11 17:58 +0200
  Re: late binding "Elizabeth D. Rather" <erather@forth.com> - 2014-01-11 08:55 -1000
    Re: late binding Paul Rubin <no.email@nospam.invalid> - 2014-01-11 11:23 -0800
      Re: late binding "Elizabeth D. Rather" <erather@forth.com> - 2014-01-11 10:37 -1000
  Re: late binding Michael L Gassanenko <m_l_g3@yahoo.com> - 2014-01-13 00:01 -0800
    Re: late binding m.a.m.hendrix@tue.nl - 2014-01-13 04:18 -0800
  Re: late binding Mark Wills <markrobertwills@yahoo.co.uk> - 2014-01-13 00:51 -0800
  Re: late binding Matthias Koch <matthias.koch@hot.uni-hannover.de> - 2014-01-13 14:40 +0100
  Re: late binding anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-01-13 14:41 +0000

csiph-web