INDIRECTION IN FROZEN CODE

> F('Ham!') # Call the function that make returned

> F = make('Spam') # Label in enclosing scope is retained > def make(label): # Make a function but don't call it As we saw in Chapter 17's examples, functions can also be created and returned for use elsewhere:

INDIRECTION IN FROZEN CODE

This code simply steps through the schedule list, calling the echo function with one argument each time through (notice the tuple-unpacking assignment in the for loop header, introduced in Chapter 13).

func(arg) # Call functions embedded in containers > schedule = > for (func, arg) in schedule: Because Python compound types like these can contain any sort of object, there's no special case here, either: The following, for example, embeds the function twice in a list of tuples, as a sort of actions table. You can even stuff function objects into data structures, as though they were integers or strings. > indirect(echo, 'Argument call!') # Pass the function to another function Argument call! func(arg) # Call the passed-in object by adding () The callee may then call the passed-in function just by adding arguments in parentheses: > def indirect(func, arg): It operates on a pointer variable, and returns an l-value equivalent to the value at the pointer address. one with a single operand) found in C-like languages that include pointer variables. I think a great deal of what goes on in society could be described that way – that it may well be fatal, but it’s not serious.Because arguments are passed by assigning objects, it's just as easy to pass functions to other functions as arguments. The dereference operator or indirection operator, sometimes denoted by (i.e. You may not want to talk about this.” Freud’s answer was, “This cancer may be fatal, but it’s not serious.” And actually, of course, it was just a lot of cells growing. The person said, “Perhaps I’d better not talk to you, because you’ve got this cancer which is very serious. Somebody came up to him and wanted to talk to him about a point in psychology. There is a story about Freud when he had cancer of the mouth. It is not a dialogue if you are not – not in the way I’m using the word. But in a dialogue you have to be serious. It teaches you not to be very serious – that there are all sorts of incoherent things, and there is nothing that can be done about it, and that you will only stir yourself up uselessly by being serious. A great deal of our whole life is not serious. Likewise, if you are trying to avoid something unpleasant inside of yourself, that is also not being serious. “On the whole, you could say that if you are defending your opinions, you are not serious. And without it there is evidently no ground from which anything can grow.” So his ability to see something new and original gradually dies away. At work, he learns in a similar way, so as to make a living, or for some other utilitarian purpose, and not mainly for the love of the action of learning itself. In school, he learns by repetition to accumulate knowledge, so as to please the teacher and pass examinations. As the child grows older, however, learning takes on a narrower meaning. In this way, he spends his first few years in a wonderfully creative way, discovering all sorts of things that are new to him, and this leads people to look back on childhood as a kind of lost paradise. Thus it is well known that a child learns to walk, to talk, and to know his way around the world just by trying something out and seeing what happens, then modifying what he does (or thinks) in accordance with what has actually happened. Rather, he must be able to learn something new, even if this means that the ideas and notions that are comfortable or dear to him may be overturned.īut the ability to learn in this way is a principle common to the whole of humanity. One prerequisite for originality is clearly that a person shall not be inclined to impose his preconceptions on the fact as he sees it. Perhaps, then, it will be best to hint at it obliquely and by indirection, rather than to try to assert positively what it is. Indeed, to define originality would in itself be a contradiction, since whatever action can be defined in this way must evidently henceforth be unoriginal. “But what is quality of originality? It is very hard to define or specify.

Indirection in frozen