I have made a few posts on the forum regarding my feature request for
a command
"What table Does set belong"
I had an "AH HA!" type moment after my last post.
rather then the code that Jermey posted here, and similar code Jeorg
posted on the forum. Both of which looped over all tables attempting to
find a situation where unioning an unknown set and a known set (created
in the loop) did NOT create an error. I posted some pseudo code on how
to go about getting set information for ourselves.
It was while writing the pseudo code that it occurred to me it should
not be too hard to write code to track sets so I CAN get validation
information about wether a set exists or if 2 sets are from the same
table etc.
I will in the next couple of days post either source, or a component
(v13 - should be convertible to any newer version), probably to
4DToday.com
however here is the outline of that code base (if interested let me
know):
//basic functionality - adds set name and pointer to table to IP arrays
- utl_sets_Create_Set (->table;"Setname") -> errors if any (text)
- utl_sets_Create_Empty_Set (->table;"Setname") -> errors if any (text)
- utl_sets_Clear_Set ("Setname1" {;"Setname2";..."SetnameN"})
(clears all set names passed - removes from IP arrays if they are
found)
//New functionality - things we could NOT do before,
//because we can lookup the set name or table pointer
//REQUIRES sets created by one of the above methods
- utl_sets_On_Same_Table ("Setname1";"Setname2") -> boolean are the
sets from same table
- utl_sets_Does_Set_Exist ("Setname1" {;"Setname2";..."SetnameN"}) ->
boolean (all) set(s) exist
- utl_sets_What_Table ("Setname") -> pointer to table (or Nil)
- utl_sets_What_Sets (->Table1;->Error_text) -> list of sets found for
table
// possible inclusions
- utl_sets_Union ("Setname1";"Setname2" {;"clear 2nd"}) - unions 2 sets
to first, possibly clears 2nd
- utl_sets_Difference ("Setname1";"Setname2" {;"clear 2nd"}) -
differences 2 sets to first, possibly clears 2nd
- utl_Intersection ("Setname1";"Setname2" {;"clear 2nd"}) - intersects
2 sets to first, possibly clears 2nd
- utl_sets_Use_and_Clear ("Setname") - uses the set, then clears it
- utl_sets_Next_in_Set ("Setname) -> errors if any (text) - moves
current record to the next record in set
(useful for iterating over a set)
retro fitting should not be too hard.
a find and replace in Design of:
- "Create set(" with "utl_sets_Create_Set(->"
- "Create Empty set(" with "utl_sets_Create_Empty_Set(->"
- "Clear Set(" with "utl_sets_Clear_Set("
should get you started :)
---------------
Gas is for washing parts
Alcohol is for drinkin'
Nitromethane is for racing
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