Module eetransformer

Decorator used to display and check properties of input and output nodes that are passed into a node handler.

Arguments:

   spec    --  specifier string. A specifier string is a list of command specifiers
               e.g. 'ni no co gc'. Each command spec is only two letters long.

               Commands can be chained arbitrarily with or without demlimiters.
               If you use delimiters use whitespace, colons, commas or semicolons.

   cond    --  predicate. If cond predicate is available commands will only be executed when the
               input data passed the cond filter. cond has the signature cond(node, **locals).


   kwd     --  dictionary containing actions for commands.

Commands:

   ni   --  display plain node (input)
   no   --  display plain node(s) (output)
   ci   --  display input CST
   co   --  display output CSTs
   cv   --  CST validation test
   so   --  unparsed python source output
   si   --  unparsed python source input
   sn   --  unparsed python source of input node after
            transformation. Used when input node is modified.
   r1   --  check that result is a single node
   r>   --  check that result is a list of nodes
   r=   --  check that result node ids equals input node id
   r!   --  check that result node ids not equals input node id
   fi   --  arbitrary test function of one argument
            executed on node input
   fo   --  arbitrary test function of one argument
            executed on node list output

Use:

   @transform_dbg("ni cv r1")
   def foo(self, node):
       ...

   @transform_dbg("r>soco")
   def bar(self, node):
       ...

   def raises(ln):
       if ln>1:
           raise ValueError("Only one output argument expected")

   @transform_dbg("r1,co", 'r1' = raises)
   def bar(self, node):
       ...