From: dxforth@gmail.com
On 29/04/2025 7:32 pm, albert@spenarnc.xs4all.nl wrote:
> In article ,
> dxf wrote:
>> On 28/04/2025 8:39 pm, Hans Bezemer wrote:
>>> On 28-04-2025 11:22, dxf wrote:
>>>> On 27/04/2025 8:28 pm, Hans Bezemer wrote:
>>>>> ...
>>>>> Just a shame the very basics are missing. The only thing holding
>> Forth back is the refusal to abstract strings. Wanna make it a counted
>> string with a cell count? Do it. Wanna keep on doing counted strings? Do
>> it. Wanna do ASCIIZ strings? No problem.
>>>>
>>>> But aren't string primitives a la ANS-Forth the key to flexibility?
>> I've used
>>>> the concatenation primitive +STRING ( a u a2 u2 -- a2 u+u2 )
>> countless times.
>>>>
>>>> : ZPLACE ( c-addr u c-addr2 -- ) zcount +string + 0 swap c! ;
>>>>
>>>> : ZAPPEND ( c-addr u c-addr2 -- ) zcount + zplace ;
>>>
>>>
>>> The problem is: it's defined nowhere. Not in Wil Baden Toolbelt, not
>> in ANS Forth, Forth 2012 -
>>
>> +STRING was defined in the Open Terminal Architecture spec - a joint project
>> by Forth Inc and MPE circa 2000.
>>
>> +STRING plus-string
>>
>> ( c-addr1 len1 c-addr2 len2 - c-addr2 len3 )
>>
>> Append the string at c-addr1, for len1 bytes, to the end of the string
>> at c-addr2, for len2 bytes. Return the beginning of the destination
>> string (c-addr2) and the sum of the two lengths (len3). It is the
>> programmer's responsibility to ensure that there is room at the end of
>> the destination string to hold both strings.
>>
>> Why it never made it into their forth offerings I don't know - perhaps
>> because the project was moth-balled?
>
> It is inferior to a $! $@ $+! scheme.
> A stored string must remember its length.
Not if it's a basic move ...
: >PAD ( a u -- a2 u ) pad 0 +string ;
: +EXT ( a1 u1 a2 u2 -- a3 u3 )
2over /ext if 2drop end 3 min s" ." 2rot -trailing
(pfsiz-5) min zbuf @ 1+ 0 +string +string +string ;
--- SoupGate-DOS v1.05
* Origin: you cannot sedate... all the things you hate (1:229/2)
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