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Explodes each list member on each input feature out into its own feature.

Any attributes on the list are demoted to become non-list attributes of the feature output. In addition, the element number of the attributes in the original list is added to the feature. Each feature's output has a copy of the geometry from the original input feature.

Input Ports

Output Ports


Attribute Accumulation

If attributes on the incoming and original feature share the same name, but are not geometry attributes that start with fme_, then they are deemed conflicted.

Usage Notes

  • If Input attributes and list element attributes have the same name, the Input attributes will be overwritten by the list element attributes.
  • ListExploder will not work with an invalid list, such as one that doesn't start at entry 0. For example:
Valid List Invalid List
mylist{0}.attr1 mylist{1}.attr1
mylist{1}.attr1 mylist{2}.attr1
mylist{2}.attr1 mylist{3}.attr1
mylist{3}.attr1 mylist{4}.attr1


Example 1:

If this feature enters this transformer:

somelist{0}.length = 7.3

somelist{0}.kind = ’paved’

somelist{1}.length = 8.4

somelist{1}.kind = ’smooth’

somelist{1}.lanes = 2

somelist{2}.length = 1.1

somelist{2}.kind = ’rough’

another_attr = ’something else’

then, presuming that the list name specified was somelist{}, the index attribute was element_num, and the Accumulation Mode parameter was set to Merge Incoming List, the first returned feature would look like:

length = 7.3

kind = ’paved’

element_num = 0

another_attr = ’something else’

If the Accumulation Mode parameter was set to Only Use Incoming List, the first returned feature would look like:

length = 7.3

kind = ’paved’

element_num = 0

Example 2:

Suppose you have a Input feature with the following 6 attributes. (The List Attribute used here would be ID{}.)







Merge Incoming List will produce elements with 4 attributes:





Only Use Incoming List will produce elements with 2 attributes:



Editing Transformer Parameters

Using a set of menu options, transformer parameters can be assigned by referencing other elements in the workspace. More advanced functions, such as an advanced editor and an arithmetic editor, are also available in some transformers. To access a menu of these options, click beside the applicable parameter. For more information, see Transformer Parameter Menu Options.

Transformer Categories


Additional Resources

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