dynamically inserting function into an object

[michael]

Hi,

below is a snipplet that could be seen as a part of a spreadsheet with
getter and setter properties and a way how to dynamically insert
function to be used when setting the value of a "cell" instance


import new
import inspect

class Cell (object):

def __init__ (self, initialvalue = 0):
self._func = None
self.__value = initialvalue

def setvalue (self, newvalue):
if self._func:
self.__value = self._recalcula te (newvalue)
else:
self.__value = newvalue

def getvalue (self):
return self.__value

def _recalculate (self, value):

ret_value = self._func (value)

return ret_value

def delvalue (self):
del self.__value


value = property(getval ue, setvalue, delvalue, "I'm the 'value'
property.")

def curry(self, func, *args):
self._func = new.function(fu nc.func_code, func.func_globa ls,
argdefs=args)

func = property(curry, "I'm the 'func' property.")

def func (value, firstcell, secondcell):
return value + firstcell.value + secondcell.valu e

cell0 = Cell (10)
cell1 = Cell (20)

curriedcell = Cell (100)

print "uncurried initial %d " % (curriedcell.va lue)

curriedcell.val ue = 60

print "uncurried set %d " % (curriedcell.va lue)

curriedcell.cur ry (func, cell0, cell1)
curriedcell.val ue = 62

print "curried set %d " % (curriedcell.va lue)



Is there a better way to do this or am I totally on the wrong way ?

Regards

Michael

[John Roth]

Re: dynamically inserting function into an object

If what you want is to insert a method into an
instance, look at new.instancemet hod.

John Roth

"michael" <michael.bieren feld@web.de> wrote in message
news:f11c8440.0 501130808.6c50a 62b@posting.goo gle.com...[color=blue]
> Hi,
>
> below is a snipplet that could be seen as a part of a spreadsheet with
> getter and setter properties and a way how to dynamically insert
> function to be used when setting the value of a "cell" instance
>
>
> import new
> import inspect
>
> class Cell (object):
>
> def __init__ (self, initialvalue = 0):
> self._func = None
> self.__value = initialvalue
>
> def setvalue (self, newvalue):
> if self._func:
> self.__value = self._recalcula te (newvalue)
> else:
> self.__value = newvalue
>
> def getvalue (self):
> return self.__value
>
> def _recalculate (self, value):
>
> ret_value = self._func (value)
>
> return ret_value
>
> def delvalue (self):
> del self.__value
>
>
> value = property(getval ue, setvalue, delvalue, "I'm the 'value'
> property.")
>
> def curry(self, func, *args):
> self._func = new.function(fu nc.func_code, func.func_globa ls,
> argdefs=args)
>
> func = property(curry, "I'm the 'func' property.")
>
> def func (value, firstcell, secondcell):
> return value + firstcell.value + secondcell.valu e
>
> cell0 = Cell (10)
> cell1 = Cell (20)
>
> curriedcell = Cell (100)
>
> print "uncurried initial %d " % (curriedcell.va lue)
>
> curriedcell.val ue = 60
>
> print "uncurried set %d " % (curriedcell.va lue)
>
> curriedcell.cur ry (func, cell0, cell1)
> curriedcell.val ue = 62
>
> print "curried set %d " % (curriedcell.va lue)
>
>
>
> Is there a better way to do this or am I totally on the wrong way ?
>
> Regards
>
> Michael[/color]

[hanz]

Re: dynamically inserting function into an object

# class Cell(object):
# def __init__(self, initialvalue = 0):
# self._func = lambda x: x
# self.__value = initialvalue
#
# def setvalue (self, newvalue):
# self.__value = self._func(newv alue)
#
# def getvalue (self):
# return self.__value
#
# def delvalue (self):
# del self.__value
#
# value = property(getval ue, setvalue, delvalue, "I'm the 'value'
property.")
#
# def curry(self, func, *args):
# self._func = lambda x: func(x, *args)

[michael.bierenfeld@web.de]

Re: dynamically inserting function into an object

*damn* it :-) python rocks.
thx

michael .oO (resetting c/c++/java crap collected over the years)