Hi all

I am new to python but not programming (Although rusty) and am using
Learning Python The Hard Way. I really like it.

Debian 8 (jessie)
KDE Desktop

Python 2.7 (It's going to be a while before 2,7 goes away. There is just
too much code out there.

Ninja-IDE IDE - I like this a lot. I can't seem to find out how to put
breaks into the code though. The debugger plugin is installed.

For some reason lesson 39 is hanging and I can't find the cause. A print
statement inserted into the get_slot function just after bucket shows
that get_bucket is returning an []. It' not surprising that enumerate()
doesn't like this very much. I just can't find the cause.

The error message is as follows:
Running: /root/mystuff/mystuff/ex39_test.py (Wed Sep 9 09:57:51 2015)

Traceback (most recent call last):
    File "/root/mystuff/mystuff/ex39_test.py", line 6, in <module>
      hashmap.set(states, 'Oregon', 'OR')
    File "/root/mystuff/mystuff/hashmap.py", line 50, in set
      i, k, v = get_slot(aMap, key)
TypeError: 'NoneType' object is not iterable

Execution Successful!

NOTE: Line 50 is the - i, k, v = get_slot(aMap, key)- of def set.
The calling code is:
# -*- coding: utf-8 -*-
import hashmap

# creat a mapping of stat to abbreviation
states = hashmap.new()
hashmap.set(states, 'Oregon', 'OR')

The hashmap code is as follows:
def new(num_buckets%6):
      """Initializes a Map with the given number of buckets."""
      aMap = []
      for i in range(0, num_buckets):
      return aMap

def hash_key(aMap, key):
      """Given a key this will create a number and then convert it to
      an index for the aMap's buckets."""
      return hash(key) % len(aMap)

def get_bucket(aMap, key):
      """Given a key, find the bucket where it would go."""
      bucket_id = hash_key(aMap, key)
      return aMap[bucket_id]

def get_slot(aMap, key, default=None):
      Returns the index, key, and value of a slot found in a bucket.
      Returns -1, key, and default (None if not set) when not found.
      bucket = get_bucket(aMap, key)

      for i, kv in enumerate(bucket):
          k, v = kv
          if key == k:
              return i, k, v

      return -1, key, default

def get(aMap, key, default=None):
      """Gets the value in a bucket for the given key, or the default."""
      i, k, v = get_slot(aMap, key, defaultÞfault)
      return v

def set(aMap, key, value):
      """Sets the key to the value, replacing any existing value."""
      bucket = get_bucket(aMap, key)
      i, k, v = get_slot(aMap, key)

      if i >= 0:
          # the key exists, replace it
          bucket[i] = (key, value)
          # the key does not, append to create it
          bucket.append((key, value))

def delete(aMap, key):
      """Deletes the given key from the Map."""
      bucket = get_bucket(aMap, key)

      for i in xrange(len(bucket)):
          k, v = bucket[i]
          if key == k:
              del bucket[i]

def list(aMap):
      """Prints out what's in the Map."""
      for bucket in aMap:
          if bucket:
              for k, v in bucket:
                  print k, v

Very frustrating and probably a stupid error. Any help will be sincerely

Gary R.

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grouppython-list @
postedSep 9, '15 at 5:27p
activeSep 10, '15 at 6:42a



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