New submission from Will Seaver <>:

In general, this is where my big problems began. My understanding of the
traversal algorithm was completely stymied by one thing: a lack of knowledge
about the __getitem__ method. If I understood this one piece of the puzzle
better, the whole thing would fall into place for me. I could glean some
information without understanding __getitem__, but without that knowledge, I
could not completely understand. With that out of the way, on to the line by
line notes:

The analogy given on p. 62 was very helpful toward what understanding I do have
of traversal now. Thank you very much for that; it helped me to understand the
brute force nature of the protocol much better.

In the example url given on p. 62 (, 'a' is
the root object, 'b' is the view name and 'c' is the context, correct?

p. 69: "Let's say that view lookup finds no matching view type. In this
circumstance, the repoze.bfg router returns the result of the not found view and
the request ends." I did not understand this at the time, but later reading
revealed the existence of the not_found view, and now I've got it.
Definitions needed:
object graph (p. 61: "It [traversal] is the act of finding a context and a view
name by walking over an object graph...") this has something to do with the correct?
container node and leaf node (p. 65: "The object graph consists of container
nodes and leaf nodes.") Container nodes have children and leaf nodes do not, 

messages: 352
nosy: kwseaver
priority: wish
status: unread
title: chapter 7
topic: bfg book

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