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Re: CfV: Quotations

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Am Mon, 22 Aug 2016 13:54:32 +0000 schrieb Anton Ertl:
> The question is how often that helps for real-world programs.  My guess
> is that, with the Pascal-like restriction, not often enough to make it
> worthwhile.  With garbage-collection of closures, it would probably be
> worthwhile, but we probably don't want to go there; and for something in
> between, we will have to see.

MINOS uses a lot of closure-like objects+quotations, the "actions".  An 
action is bound to a widget, contains a state variable of its own (e.g. 
on/off for a toggle button), and an action (or two), stored as quotation 
xt; the quotation is performed in the context of the object that created 
those actions and widgets.  Since all that commons stuff is reused again 
and again, it's just a slightly different version of [: ;] around a block 
of code to instantiate them.  So the line count is probably not a problem.

In Common Lisp, you would do that with closures.  In an OOP system, you 
do it with OOP.  And if you want a more compact format of declaring 
things, just define them.  You could have an OOP system that declares the 
class in one line, and creates you an instantiation code that takes the 
initial values from stack, just with about the same amount of code we 
need to implement locals (a lot more code than mini-oof2.fs).

<base class> O{ k x1 x2 x3 x4 x5 }O mob

certainly is possible.  There's even a mini-oof.fs based implementation 
of closures, which does just that.  If we wanted to generalize the locals 
declaration, we could easily reuse most of the code in glocals.fs; after 
all, the declaration of a set of locals and the declaration of a set of 
instance variables is the same problem: Create a bunch of names which 
address consecutive elements in memory; one time on a locals stack, 
another time in an object.  And Algol 60 even recognizes that by calling 
the locals "activation record".

If you look at the Rosetta code page of the man-or-boy test, you'll find 
a number of implementations which use classes to implement the activation 
record, so I think that approach is fair and useful.

http://rosettacode.org/wiki/Man_or_boy_test

If you want a class creation syntax which reduces line count, it's also 
doable.  mini-oof2.fs just shares code with the structure declaration, 
sharing code with the locals declaration would also be possible.

-- 
Bernd Paysan
"If you want it done right, you have to do it yourself"
net2o ID: kQusJzA;7*?t=uy@X}1GWr!+0qqp_Cn176t4(dQ*
http://bernd-paysan.de/

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CfV: Quotations anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-08-10 16:52 +0000
  Re: CfV: Quotations Matthias Trute <matthias.trute@gmail.com> - 2016-08-10 11:19 -0700
  Re: CfV: Quotations Paul Rubin <no.email@nospam.invalid> - 2016-08-10 11:55 -0700
    Re: CfV: Quotations Bernd Paysan <bernd.paysan@gmx.de> - 2016-08-14 20:52 +0000
      Re: CfV: Quotations hughaguilar96@gmail.com - 2016-08-14 14:42 -0700
        Re: CfV: Quotations Julian Fondren <julian.fondren@gmail.com> - 2016-08-14 16:43 -0700
      Re: CfV: Quotations Paul Rubin <no.email@nospam.invalid> - 2016-08-15 22:16 -0700
        Re: CfV: Quotations anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-08-16 07:13 +0000
          Re: CfV: Quotations Paul Rubin <no.email@nospam.invalid> - 2016-08-18 15:30 -0700
            Re: CfV: Quotations anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-08-19 15:32 +0000
          Re: CfV: Quotations Bernd Paysan <bernd.paysan@gmx.de> - 2016-08-20 20:46 +0000
            Re: CfV: Quotations anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-08-21 09:32 +0000
              Re: CfV: Quotations hughaguilar96@gmail.com - 2016-08-21 11:06 -0700
                Re: CfV: Quotations anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-08-24 17:02 +0000
              Re: CfV: Quotations Bernd Paysan <bernd.paysan@gmx.de> - 2016-08-21 22:52 +0000
                Re: CfV: Quotations anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-08-22 13:54 +0000
                Re: CfV: Quotations Bernd Paysan <bernd.paysan@gmx.de> - 2016-08-22 23:19 +0000
                Re: CfV: Quotations anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-08-24 15:54 +0000
                Re: CfV: Quotations Bernd Paysan <bernd@net2o.de> - 2016-08-28 00:43 +0000
                Re: CfV: Quotations anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-08-28 09:53 +0000
                Re: CfV: Quotations Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-08-28 08:32 -0500
                Re: CfV: Quotations anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-08-28 14:38 +0000
  Re: CfV: Quotations mhx@iae.nl - 2016-08-10 12:02 -0700
  Re: CfV: Quotations Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2016-08-11 17:25 +0100
  Re: CfV: Quotations Julian Fondren <julian.fondren@gmail.com> - 2016-08-11 12:48 -0700
  Re: CfV: Quotations minforth@arcor.de - 2016-08-16 03:31 -0700
  Re: CfV: Quotations Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2016-08-31 15:15 +0100
    Re: CfV: Quotations anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-08-31 15:26 +0000
      Re: CfV: Quotations Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2016-09-02 22:33 +0100
        Re: CfV: Quotations anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-09-03 06:47 +0000

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