shift list and return first element.
arguments:
- inputlist (list)
list to be shifted
results:
- set inputlist to 2nd to last elements of original inputlist
- return first element in inputlist
example:
>>> import decida
>>> lst = [1, 2, 4, 5, 9]
>>> a = decida.lshift(lst)
>>> print "a =", a, ", lst =", lst
'a = 1 , lst = [2, 4, 5, 9]'
notes:
lshift command used extensively in Tcl scripts, but pythonic lhs = inputlist.pop(0) is just as simple