szabi wrote: > I have a list of three values and want to call a function with four > parameters. I would like > to write something like: > > a = [1, 2, 3] > f(*a, 4) > > This is syntactically wrong, so is there a function which appends a > value to a list and > returns the new value, so that I could write something like this: > > f(list(a).functional_append(4)) > > I can't modify 'a'.
Two more options: if you know the name of the function's fourth parameter you can mix keyword and positional arguments >>> def f(a, b, c, d): ... return "f(a=%r, b=%r, c=%r, d=%r)" % (a, b, c, d) ... >>> a = [1, 2, 3] >>> f(d=42, *a) 'f(a=1, b=2, c=3, d=42)' or you can use partial function application: >>> def partial(f, *left): ... def w(*right): ... return f(*left+right) ... return w ... >>> partial(f, *a)(42) 'f(a=1, b=2, c=3, d=42)' A generalized version of partial() will become part of the standard library in Python 2.5. Peter -- http://mail.python.org/mailman/listinfo/python-list
