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Re: When to use !name vs. name! ?

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Coos Haak wrote:
> Op Mon, 20 Mar 2017 09:41:11 +1100 schreef HAA:
>
> > rickman wrote:
> >> On 3/18/2017 7:47 PM, HAA wrote:
> >>> rickman wrote:
> >>>> On 3/17/2017 7:08 PM, Elizabeth D. Rather wrote:
> >>>>> ...
> >>>>> It depends on the word. Words that simply fetch a value from a variable
> >>>>> aren't substantive enough to justify separates @/! definitions, so it
> >>>>> really depends on what the rest of the action is. I can imagine an
> >>>>> application that uses a thermocouple, for example. The name of the port
> >>>>> that controls it is Thermo.  I would have words like !Thermo to write to
> >>>>> it and @Thermo to read it and maybe perform a calibration. I would
> >>>>> prefer to have the symbol first in these cases because it's the action
> >>>>> that's important, not the thing being acted upon.
> >>>>
> >>>> So reverse the method used across Forth because the action is important?
> >>>>   Is it really not important what it is acting on?  I think it is the
> >>>> opposite.  The noun should be first since that is the important part.
> >>>> The verb is last because it only has meaning in the context of what it
> >>>> is acting on.
> >>>> ...
> >>>
> >>> There are numerous cases where the action comes first and the object the
> >>> qualification e.g. open/close-file  read/write-line  get/set-order, begin/end-xxx.
> >>> In this context  @/!name  becomes shortform for get/set restore/save etc.
> >>> Where the action is trivial e.g. peek/poke memory then the object takes
> >>> precedence and reflects the stack order. e.g. name@/! .  Being a trivial
> >>> operation however, there may be little need for defining a such a function.
> >>
> >> But the fetch and store operations have an operator @ and !.  Usage is
> >> <name> @ or <name> !.  Combining these words into one operator the
> >> convention would be name@ or name!.  I've seen this guideline explicitly
> >> stated for cases like 1+ or 2* and many others.
> >
> > If it is advantageous for trivial functions to have names indicative of the stack
> > effect - is it not also advantageous to differentiate functions that are not simple
> > or indicative?  Forth has GET-ORDER SET-ORDER not ORDER@ ORDER!
> > because ORDER is a concept, not a memory location.
>
> Forths with the SEARCH WORDLIST have GET-ORDER and SET-ORDER
> They deliver or store a structure consisting of wid's and a number.
> I have seen implementations that had ORDER@ and ORDER!
> Those were synonyms of (FigForth) CONTEXT @ and CONTEXT ! respectively.

CONTEXT was a simple variable where a trailing @/! operator was appropriate.
GET/SET-ORDER reflects a more complex function where the emphasis is on
the action, not the object.

> Another example. I have a pointer that gives its value by saying
> MYPTR and setting to another value by >MYPTR .
> The first is used more often, so writing of MYPTR> is distracting.
>
> groet Coos

The opposite of >MYPTR would typically be named <MYPTR.  Relevant here is
how the action (to/from) precedes the object.

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Thread

When to use  !name  vs.  name! ? "HAA" <someone@microsoft.com> - 2017-03-14 11:15 +1100
  Re: When to use  !name  vs.  name! ? hughaguilar96@gmail.com - 2017-03-13 18:27 -0700
    Re: When to use  !name  vs.  name! ? Mark Wills <markwills1970@gmail.com> - 2017-03-14 01:33 -0700
  Re: When to use  !name  vs.  name! ? Mark Wills <markwills1970@gmail.com> - 2017-03-14 01:30 -0700
  When to use  !name  vs.  name! ? NN <november.nihal@gmail.com> - 2017-03-14 02:56 -0700
    Re: When to use  !name  vs.  name! ? "HAA" <someone@microsoft.com> - 2017-03-16 08:59 +1100
      Re: When to use  !name  vs.  name! ? Mark Wills <markwills1970@gmail.com> - 2017-03-16 02:11 -0700
        Re: When to use  !name  vs.  name! ? "HAA" <someone@microsoft.com> - 2017-03-17 11:19 +1100
  Re: When to use !name vs. name! ? rickman <gnuarm@gmail.com> - 2017-03-16 20:46 -0400
    Re: When to use !name vs. name! ? "Elizabeth D. Rather" <erather@forth.com> - 2017-03-16 21:34 -1000
      Re: When to use !name vs. name! ? "HAA" <someone@microsoft.com> - 2017-03-18 09:49 +1100
        Re: When to use !name vs. name! ? "Elizabeth D. Rather" <erather@forth.com> - 2017-03-17 13:08 -1000
          Re: When to use !name vs. name! ? rickman <gnuarm@gmail.com> - 2017-03-17 19:35 -0400
            Re: When to use !name vs. name! ? Mark Wills <markwills1970@gmail.com> - 2017-03-18 00:51 -0700
            Re: When to use !name vs. name! ? "HAA" <someone@microsoft.com> - 2017-03-19 10:47 +1100
              Re: When to use !name vs. name! ? rickman <gnuarm@gmail.com> - 2017-03-18 22:18 -0400
                Re: When to use !name vs. name! ? "Elizabeth D. Rather" <erather@forth.com> - 2017-03-18 16:36 -1000
                Re: When to use !name vs. name! ? rickman <gnuarm@gmail.com> - 2017-03-18 23:53 -0400
                Re: When to use !name vs. name! ? "Elizabeth D. Rather" <erather@forth.com> - 2017-03-18 22:22 -1000
                Re: When to use !name vs. name! ? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-03-19 16:03 +0000
                Re: When to use !name vs. name! ? Alex <alex@rivadpm.com> - 2017-03-19 17:42 +0000
                Re: When to use !name vs. name! ? "Elizabeth D. Rather" <erather@forth.com> - 2017-03-19 13:10 -1000
                Re: When to use !name vs. name! ? albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-03-19 13:34 +0100
                Re: When to use !name vs. name! ? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-03-19 16:23 +0000
                Re: When to use !name vs. name! ? albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-03-19 20:47 +0100
                Re: When to use !name vs. name! ? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-03-20 03:47 -0500
                Re: When to use !name vs. name! ? "HAA" <someone@microsoft.com> - 2017-03-20 09:41 +1100
                Re: When to use !name vs. name! ? Coos Haak <htrofhc@gmail.com> - 2017-03-20 01:24 +0100
                Re: When to use !name vs. name! ? "HAA" <someone@microsoft.com> - 2017-03-21 12:10 +1100
                Re: When to use !name vs. name! ? hughaguilar96@gmail.com - 2017-03-20 18:45 -0700
                Re: When to use !name vs. name! ? Coos Haak <htrofhc@gmail.com> - 2017-03-21 14:58 +0100
                Re: When to use !name vs. name! ? "HAA" <someone@microsoft.com> - 2017-03-22 19:49 +1100
          Re: When to use !name vs. name! ? hughaguilar96@gmail.com - 2017-03-17 16:46 -0700
  Re: When to use  !name  vs.  name! ? Lars Brinkhoff <lars.spam@nocrew.org> - 2017-04-12 08:13 +0200

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