Re: Parsing timestamps?

On 30/10/2024 12:45 am, Hans Bezemer wrote:

On 29-10-2024 10:25, dxf wrote:

On 29/10/2024 4:07 am, Hans Bezemer wrote:

...
I have put the complication elsewhere. If we assume we're working in decimal, you don't even need >NUMBER:
>
char 0 negate +constant 0-
>
: /int    ( a1 n1 -- a2 n2 n3)
   0 >r 1 >r 1- chars over +
   begin
    over 1- over <
   while
     dup c@ is-digit
   while
     dup c@ 0- r> tuck * r> + >r 10 * >r 1-
   repeat over - rdrop r> -rot
;
...

>
So that's how to convert a numeric string from the other end.
Nice!  Easier than I imagined it would be.

 
TORS is the multiplier, 2ORS is the accumulator. Normally, the multiplier is multiplied after each run with BASE @ - but that makes little sense when IS-DIGIT isn't properly adjusted. Would be a nice exercise, though.

Something like this...

\  \CHAR ( a u -- a u-1 c )
\  >DIGIT ( c base -- u -1 | c 0 )

: /INT ( a1 n1 -- a2 n2 u )                                    
  0 >r  1  begin  >r  dup while                                
    \char  base @ >digit  while                                   
    r> tuck  *  r> + >r  base @ *                                 
  repeat  drop ( -1 /string)  then  rdrop  r> ;

OTOH the necessity to convert R-L is probably rare.