Now that you have a message definition, the next step is to create the transformation script for it. Like all scripts in Chameleon, this script is written in Python.

In this section, you will create a transformation script that removes Z-segments from the incoming HL7 messages and executes any scripts that have been defined for the message segments.

To create this transformation script:

• In the Message Definitions section of the Workspace, locate the Default (Person Update) message definition that you have just created.
• Double-click Transformation Script. The Editing Script window appears:

Editing Script Window

• In this window, type (or paste) the following Python code:

current_segment = environment.input_segment_iterator()
current_segment.apply_transform()
output = current_segment.output()

while current_segment.move_one():
   # append each segment which is not a Z-segment
   if current_segment.segment_id()[0] <> 'Z': 
      current_segment.apply_transform()  # apply segment scripts
      output = output + current_segment.output()

value = output

• Click Ok. The transformation script is now created.

The Python script shown above examines each segment of the script in turn:

• If the segment ID starts with Z, the segment is skipped.
• Otherwise, the script calls apply_transform(), which executes the scripts that have been created for this segment. It then calls output(), which returns the transformed segment.
• As the script is examining the segments, it builds the transformed message, which consists of the transformed segments joined together. (While it is being built, this transformed message is contained in the output variable.)

Once the transformed message is completely rebuilt, it is assigned to the value variable, which is a special variable that contains the HL7 message.

	In this example, the current_segment variable contains a Segment Iterator object, which examines each of the segments of the message in turn. For more information on this object, see Segment Iterator Object.

Now that you have created the transformation script, the next step is to create the segment scripts that this transformation script will execute. These segment scripts will replace patient names with the string fff.