Is it

  set ip address 1, 10.1.9.4

Or

  ipaddress[1] := 10.1.9.4

?

This distinction should be captured in a grammar, not embedded deep within parsing code.

'''Advantages'''

Multiple alternative interfaces to the same subsystem become possible.  Easier to integrate into other systems.

'''Things to consider'''

Limitations in the internal representation of parsed expressions or in the parser's capabilities may show in the syntax exposed to the end user.

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FactorFinding CategoryRefactoring