
  collapse_child - Collapses a parent (which is the current node) and a given
  child node into the parent
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   collapse_child [-h] [-v] <child_instance_name>

   This  command  collapses  the given child into the current node. After
   this command, the number of children of the current node will decrease
   by  one.  The  variables  in the child node will be renamed to reflect
   their  original  name. For example, if the current node is named "foo"
   and it has two children, "bar1" and "bar2", then after

   collapse_child bar1

   is  executed,  the  name  of any variable occuring in bar1, say "xvar"
   will  be renamed "bar1$xvar". The new parent will have only the single
   child "bar2" (which can be seen by typing "ls").

   The  user  can  use  "cd"  to traverse a hierarchy, go to a particular
   node. When the user uses "write_blif" from a particular node, vis will
   write the circuit in this node out. However, the user might want to do
   synthesis  on  the  entire circuit in the hierarchy. In that case, the
   hierarchy  can  be  collapsed  into a single node, by repeatedly using
   this command.

   Examples:

   collapse_child P1

   Collapse P1 into the current node.

   Command options:

   -h
          Print the command usage.

   -v
   Verbose mode.
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   Last updated on 20050519 10h16
