[postgis-tickets] [PostGIS] #1987: Results given by ST_Simplify inconsistent between PostGIS 1.5.2 and 2.0.1

[PostGIS]

#1987: Results given by ST_Simplify inconsistent between PostGIS 1.5.2 and 2.0.1
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  Reporter:  ChrisInCambo  |       Owner:  pramsey      
      Type:  defect        |      Status:  reopened     
  Priority:  blocker       |   Milestone:  PostGIS 2.0.3
 Component:  postgis       |     Version:  2.0.x        
Resolution:                |    Keywords:  history      
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Comment(by robe):

 I think trying to introduce a GUC in a micro is also a no-no since it
 changes the user-front facing api.

 However as long as we don't as part of what we call "2.0", introduce a new
 user facing api we call "part of 2.0",  there is nothing that prevents us
 from say providing a supplemental script -- introducing that little flag
 (which maybe you have in the C api already), and exposing it in the legacy
 function (as the default behavior).  I think it may be so legacy that we
 wouldn't really have it as part of our core legacy script.  More like we
 have the gist index one as a separate file altogether, to distance
 ourselves from the dirtiness of it. :)

 Keep in mind that whenever people upgrade their scripts, it would modify
 their install to new behavior (unless it was called something different
 from ST_Simplify like ST_LegacySimplify). So the only issue is whether
 people would be satisfied with a legacy function with a different name.  I
 think that is legit because all the legacy functions we have none of them
 are names we consider part of 2.0 except they were in 1.5.  But then it's
 people's business whether they go in and then rename it the old name so
 they don't need to change their apps.  I'll also just look the other way
 :).

 Hmm I'm beginning to sound like a politician, I might need to take a long
 hot shower. How do we break/bend the rules without technically breaking
 the rules.


 Then in 2.1 we introduce a GUC that allows people to set all sorts of
 legacy as their preferred behavior and default args that can be overridden
 for one-off application requirements.

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/1987#comment:35>
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