/utilagset.txt 
\ Set aggregation                                                    vandys

\ Much like an "AgBtree" creates an aggregate view of a list of B-trees,
\  an "AgSet" creates an aggregate view of a list of sets.
only extensions definitions

AgView -> subclass: AgSet


















\ Set aggregation                                                    vandys

variable doFn scrLocal   variable aglist scrLocal   variable idx scrLocal

: already? ( key -- ? )   idx @ 0 ?do   dup i aglist @ -> @
      -> in? if   unloop drop true exit   then
   loop   drop false ; scrLocal
: (do) ( arg key -- )   dup already? if   2drop exit   then
   doFn @execute ; scrLocal
AgSet -> :method do ( arg 'fn self -- )   swap doFn !
   ag>list dup aglist !   -> size 0 ?do
      ( arg ) dup   i dup idx !   aglist @ -> @ ( arg arg set )
      ['] (do) swap -> do   loop drop method;












\ Set aggregation; testing                                           vandys
false [if] \ Testing

Set -> new constant s1   Set -> new constant s2
AgSet -> new constant as   s1 as -> agadd   s2 as -> agadd
1 s1 -> add   2 s1 -> add   3 s1 -> add
100 s2 -> add   101 s2 -> add   102 s2 -> add
200 as -> add
300 s1 set!   300 s2 set!

12321 constant KEY
: andy ( arg key -- )   . KEY - abort" Key mismatch" ;
: t1   KEY ['] andy as1 agsetDo ;

as -> free

[then] \ Testing