The Table Grammar represents the internal structure of the
message. Chameleon is designed to protect your code from variations in
HL7 message structure. This way, changes in the message structure
and moving a particular piece of data from one segment to another
will not require code changes.
That's why applications that use Chameleon do not
directly access the message fields, but instead use the tables to
determine which message fields should be mapped. In object-oriented
programming terms, Chameleon encapsulates the message structure; thus
shielding your application from changes.