dict duplicity

[Paolino]

Randy Bush wrote:
> a dict written as
> 
>    pKey = (prefix, pLen, origin)
> 
>    val = dict.get(pKey)
>    if val == None:
>       dict[pKey] = (timeB, timeB)
>    else:
>       if val[0] > timeB:  val[0] = timeB
>       if val[1] < timeB:  val[1] = timeB
>       dict[pKey] = val
> 
> and read back as
> 
>    for pKey, pVal in dict.iteritems():
>       print \
>          pKey[0], hash(pKey[0]), \
>          pKey[1], hash(pKey[1]), \
>          pKey[2], hash(pKey[2]), \
>          "hash=", hash(pKey), \
>          pVal[0], hash(pVal[0]), \
>          pVal[1], hash(pVal[1])
> 
> when run with | sort, produces
> 
> 12.0.0.0 -2054516913 8 8 7018 329707286 hash= -604503432 917088000 917088000 917088000 917088000
> 12.0.0.0 -2054516913 8 8 7018 329707286 hash= -604503432 917088000 917088000 917088000 917088000
> 12.0.0.0 -2054516913 8 8 7018 329707286 hash= -604503432 917088000 917088000 917088000 917088000
> 12.0.0.0 -2054516913 8 8 7018 329707286 hash= -604503432 917088000 917088000 917088000 917088000
> 12.0.0.0 -2054516913 9 -1293912648 7018 329707286 hash= -1578430040 917088000 917088000 917088000 917088000
> 12.0.0.0 -2054516913 9 -1293912648 7018 329707286 hash= -1578430040 917088000 917088000 917088000 917088000
> 
> not that there are two entries with the same hash=
> 
> i am utterly confused
> 
> randy
> 
I'm not sure I got your question but having the same hash(key) is not 
having the same key for a dict.

 >>> {-1:0,-2:0}
{-2: 0, -1: 0}
 >>> hash(-1)!=hash(-2)
False

A key lookup in a dict involve real keys comparisons via '==' among the 
keys of the bin identified by the hash of the key.


Regard Paolino

		
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