RosettaCodeData/Task/Date-manipulation/Standard-ML/date-manipulation-1.ml
2023-07-01 13:44:08 -04:00

21 lines
1 KiB
Standard ML

val smltime= fn input => (* parse given format *)
let
val mth::day::year::itime::t = String.fields Char.isSpace input ;
val tmp = String.fields (fn x=> x= #":") itime;
val h = (valOf(Int.fromString (hd tmp) )) + (if String.isSuffix "pm" (hd(tl tmp)) then 12 else 0 ) ;
val ms = (String.extract (hd (tl tmp), 0 ,SOME 2))^":00" ;
val mth = String.extract (mth,0,SOME 3)
in
(* Sat is a dummy *)
Date.fromString ("Sat "^mth ^" " ^ (StringCvt.padLeft #"0" 2 day) ^ " "^(StringCvt.padLeft #"0" 2 (Int.toString h))^":" ^ ms^" "^ year )
end;
local
val date2real = Time.toReal o Date.toTime o valOf
val onehour = date2real ( Date.fromString "Mon Jan 01 23:59:59 1973" ) - ( date2real ( Date.fromString "Mon Jan 01 22:59:59 1973" )) ;
in
val hoursFrom = fn hours => fn from =>
(Date.fromTimeLocal o Time.fromReal)( ( date2real from) + hours * onehour );
end;