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Similarity test between objects

Hi, I've used this function for testing two objects similar or not. May be useful for someone else.
    
     similar?: func [o [object!] p [object!]]
     [
         equal? first o first p
     ]
    
     o: context [a: 1 b: 2 c: 3]
     p: context [a: 1 b: 2 c: 3]
     same? o p ;== false
     similar? o p ;== true
    
     o: context [a: 1 b: 2 c: 3]
     p: context [a: 1 b: 2 x: 3]
     k: context [a: 1 b: 2 c: 3 d: 4]
     similar? o p ;== false
     similar? o k ;== false


posted by:   Endo       3-Aug-2010/10:19:30-7:00



Here is a better version of SIMILAR? function:
This function check two objects have same words and those values are in same types (order of words is not important):
    
     similar?: func [o [object!] p [object!]] [
         foreach word sort first p [if not equal? type? get in o word type? get in p word [return false] true]
     ]
    
Here is a quick test what it does:
    
     o: context [a: 0 e: does ["y"] b: 4]
     p: context [e: does ["x"] b: 12 a: 2]
     similar? o p
     == true
    
     o: context [a: 0 e: does ["y"] b: 4.5]
     p: context [e: does ["x"] b: 12 a: 2]
     similar? o p
     == false (b is decimal in O but integer in P
    
     o: context [a: 0 e: does ["y"] b: 4.5]
     p: context [e: does ["x"] a: 2]
     similar? o p
     == false (there is no B in P)


posted by:   Endo       4-Nov-2010/11:44:31-7:00



Minor fix, now it test both objects:
    
similar?: func [o [object!] p [object!]] [
    foreach word sort first o [if not equal? type? get in o word type? get in p word [return false]]
    foreach word sort first p [if not equal? type? get in o word type? get in p word [return false]]
    true
]


posted by:   Endo       4-Nov-2010/11:49:17-7:00



Endo, it would be great to add all your functions and short examples to rebol.org.

posted by:   Nick       7-Nov-2010/4:14:41-8:00



Thank you Nick, I'll.
    
Here is a little bit better version, it traverse just one object and doesn't check the 'self word (there is always 'self word in all objects)
    
     similar?: func [o [object!] p [object!]] [
         if not-equal? length? first o length? first p [return false]
         foreach word next first o [if not equal? type? get in o word type? get in p word [return false]]
         true
     ]


posted by:   Endo       8-Nov-2010/18:09:31-8:00