Definition classifications. Where is get_classification?

[DanRathbun]

@kengey

Yes, or you could look at the assigned attribute value:

definition.get_attribute("AppliedSchemaTypes", "IFC 2x3")

But again… isn’t this something that is missing in the api?

Oh yes, I know what you mean now. (needed a cup of coffee first)
Yes I remember this being discussed in the past. (see links below)

REF:

@DanRathbun

So, if cinst was a reference to an IFC component instance , then you’d check the IFC type:

def ifc_type_is?( comp_inst, ifc_tag )
  dict = comp_inst.definition.attribute_dictionary("AppliedSchemaTypes")
  return false if dict.nil? # nil if it doesn't exist
  return dict["IFC 2x3"] == ifc_tag ? true : false
end

then call that method:

cinst.explode if ifc_type_is?(cinst,"IfcBuildingStorey")

@jim_foltz

My question is how do you get the ifc type of the component for the path?

… has several code snippets for walking the classification attribute dictionary “trees”.

@tt_su

We don’t have any special API methods to traverse all the classification data, but you can traverse the nested set of attribute dictionaries yourself using the AttributeDictionary iterators.

---

You could use a refinement module if you like …

module Author

  module AppliedTypeForIFCDefinitions
    refine Sketchup::ComponentDefinition do
      def applied_IFC_type
        self.get_attribute("AppliedSchemaTypes", "IFC 2x3")
      end
    end
  end

  using AppliedTypeForIFCDefinitions
  
  # Code that makes calls like the following on instances ...
  
  if obj.defintion.applied_IFC_type == "IFCBuildingStory"
    # do something
  end
  
end

---

The API authors are “minimalists”. If there is a simple alternative or workaround they don’t create a dedicated method(s). Ie, more work, more maintenance, etc. (Arguing for “robustness” doesn’t work, as I’ve tried it. They’ll just quote various “golden rules of APIs” and cite bibliographic references with subjective opinions that support minimalism.)

@kengey, I suggest opening a documentation issue at the GitHub API tracker to add your snippet above, as a coding tip, to the Sketchup::ComponentDefinition#add_classification method’s YARD docstring.