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import logging
import sys
import types

# It's great to log the entering/leaving of methods and functions, but it would be way cool
# to see who gets called by the function you go into. That probably means hacking ASTs and
# finding the GOSUB bytecode.

def discover(obj, filtfunc=None):
    if filtfunc is None:

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"""
Mock is confusing as hell. Document some of it.
http://www.voidspace.org.uk/python/mock/patch.html
http://mock.readthedocs.org/en/latest/index.html
"""

import unittest
import pprint
from mock import MagicMock, patch, call

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% http://www-cdf.fnal.gov/offline/PostScript/BLUEBOOK.PDF

/xcenter 306 def
/ycenter 500 def
/scalefactor 8 def

/scale1 {
    scalefactor mul
} def

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Why not just use sysfs?

Because it's slow. Using mmap with /dev/mem is way way faster, even in Python, and zippity-quick in C.

Python-mmap on the Raspberry Pi

Based on C code by Dom and Gert at http://elinux.org/RPi_Low-level_peripherals. Using mmap is potentially much faster than http://en.wikipedia.org/wiki/Sysfs, which is what almost all RPi tutorials recommend.

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-- These examples are from http://en.wikipedia.org/wiki/Join_(SQL)

DROP DATABASE IF EXISTS dumb_example;
CREATE DATABASE dumb_example;
USE dumb_example;

CREATE TABLE department
(
  DepartmentID INT,
  DepartmentName VARCHAR(20)

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# Tail recursion in Python

# http://stackoverflow.com/questions/13591970/does-python-optimize-tail-recursion
# As far as the question, does Python inherently support tail recursion?
# No, and it never will since Guido prefers to be able to have proper tracebacks
# http://neopythonic.blogspot.com.au/2009/04/tail-recursion-elimination.html
# http://neopythonic.blogspot.com.au/2009/04/final-words-on-tail-calls.html

# But it's possible to do it with a decorator, and the stack never gets too deep.
# http://code.activestate.com/recipes/496691-new-tail-recursion-decorator/

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from math import cos, sin, atan2

class Circle:
    def __init__(self, x, y, radius):
        self.x, self.y, self.radius = x, y, radius

def intersect_circles(first, second):
    """
    >>> intersect_circles(Circle(0, 0, 1), Circle(1, 1, 1))
    ((1.5700924586837752e-16, 1.0), (1.0, 0.0))

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Fun hacks with OpenSCAD

Hack the First

Use OpenSCAD to take a slice from a 3D object and convert it to a 2D DXF file, suitable for laser cutting.

• Command line
• Slicing

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module home_depot_bucket() {
	translate([0,0,14.25])
    	difference() {
    		cylinder(h=1/4, d=14, $fn=30);
    		cylinder(h=1/4, d=12, $fn=30);
    	}
	difference() {
		cylinder(h=14.5, d1=10.5, d2=12.5, $fn=30);
		translate([0,0,1/4])
			cylinder(h=14.5, d1=10, d2=12, $fn=30);

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# Can we do a JavaScript-like .then() hack in Python?

import threading
import time


class Sleeper(threading.Thread):
    def __init__(self):
        super(Sleeper, self).__init__()
        self.f = None