mininet/mininet — pull request #328 by lantz (2014-07-11 00:47:49+00:00)
Title: Add build() method to simplify Topo() usage

This is my idea for simplifying `Topo()` subclassing, by introducing a `build()` method which can be overridden in place of `__init__()`. This makes a simple topology look like:

```python
class MyTopo( Topo ):
def build( self ):
h1, h2 = self.addHost( 'h1' ), self.addHost( 'h2' )
s1 = self.addLink( h1, h2 )
```