A library approach to the ternary operator

[David Abrahams]

I still like the idea of a ternary operator, and I'm not afraid to
admit it.  However, none of the language solutions were particularly
compelling, so I got to thinking about a library approach and came up
with this one:

      ---- ternary.py-------
      def select(x): return x[0]
      ---------------------
    # then...

      from ternary import *
      select(condition and [true_result] or [false_result])

it's just enough prettier than

      (condition and [true_result] or [false_result])[0]

to be worth using.  Having a function name ("select") there gives us
something to attach a nice verbose comment to, while the above, since
it uses only language primitives, remains obscure.

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com