[postgis-devel] [PostGIS] #1014: GEOMETRY type is not "hashable"

[PostGIS]

#1014: GEOMETRY type is not "hashable"
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 Reporter:  vince                |       Owner:  pramsey      
     Type:  defect               |      Status:  new          
 Priority:  medium               |   Milestone:  PostGIS 2.0.0
Component:  postgis              |     Version:  1.5.X        
 Keywords:  GEOMETRY hash UNION  |  
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Comment(by mcayland):

 Unfortunately structures containing IEEE-754 floating point numbers cannot
 be marked HASHABLE because of the "negative zero" problem. There is an
 explanation of this here:
 http://www.virtualdub.org/blog/pivot/entry.php?id=259.

 I suspect that this will have to be marked as a "won't fix" :(

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/1014#comment:3>
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