# definition of an Infix operator class # this recipe also works in jython # calling sequence for the infix is either: # x |op| y # or: # x <> y class Infix: def __init__(self, function): self.function = function def __ror__(self, other): return Infix(lambda x, self=self, other=other: self.function(other, x)) def __or__(self, other): return self.function(other) def __rlshift__(self, other): return Infix(lambda x, self=self, other=other: self.function(other, x)) def __rshift__(self, other): return self.function(other) def __call__(self, value1, value2): return self.function(value1, value2) # Examples # simple multiplication x=Infix(lambda x,y: x*y) print 2 |x| 4 # => 8 # class checking isa=Infix(lambda x,y: x.__class__==y.__class__) print [1,2,3] |isa| [] print [1,2,3] <> [] # => True # inclusion checking is_in=Infix(lambda x,y: y.has_key(x)) print 1 |is_in| {1:'one'} print 1 <> {1:'one'} # => True # an infix div operator import operator div=Infix(operator.div) print 10 |div| (4 |div| 2) # => 5 # functional programming (not working in jython, use the "curry" recipe! ) def curry(f,x): def curried_function(*args, **kw): return f(*((x,)+args),**kw) return curried_function curry=Infix(curry) add5= operator.add |curry| 5 print add5(6) # => 11