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@jwhiteman
jwhiteman / acl2.lisp
Created January 26, 2024 19:25
Code from Paul Graham's ANSI Common Lisp
; The code in this file was mechanically extracted from the TeX
; source files of _Ansi Common Lisp_, except for bst-remove and
; bst-delete and their subroutines, which replace broken versions
; in the book.
; If you have questions or comments about this code, or you want
; something I didn't include, send mail to lispcode@paulgraham.com.
; This code is copyright 1995 by Paul Graham, but anyone who wants
; to use it is free to do so.
@jwhiteman
jwhiteman / di.rb
Created December 3, 2017 22:16
Dumb DI container
class DIContainer
def configure
yield self
end
def method_missing(key, val)
if key =~ /=$/
key = key.to_s.chop
(class << self; self; end).class_eval do
attr_accessor key
@jwhiteman
jwhiteman / condvar_broadcast.rb
Created March 18, 2017 01:19
ruby condition variable and broadcast
m = Mutex.new
c = ConditionVariable.new
tg = ThreadGroup.new
t = 5.times.map do |n|
tg.add(Thread.new do
print "starting #{n}\n"
m.synchronize do
@jwhiteman
jwhiteman / renting_zero.rb
Last active March 14, 2017 04:23
quick connection pool example
require "thread"
require "connection_pool"
require "pp"
NUM_CLIENTS = 9
MAX_AT_A_TIME = 3
TIMEOUT = 10
JOB_TIME = 3
# we'll let people lease access to zero
@jwhiteman
jwhiteman / s3.rb
Created January 30, 2017 03:09
Basic Aws::S3::Client usage
=begin
{
"AccessKey": {
"UserName": "s3.deploy.foo",
"Status": "Active",
"CreateDate": "2016-11-04T16:25:27.123Z",
"SecretAccessKey": "secret",
"AccessKeyId": "access"
}
}
@jwhiteman
jwhiteman / dfa.exs
Created January 27, 2017 03:42
basic DFA simulation
defmodule DFA do
def accepts?(accept: accept_states, rules: rules, s: string) do
string
|> String.graphemes
|> List.foldl(1, fn(char, state) -> next(state: state, char: char, rules: rules) end)
|> member?(accept_states)
end
defp next(state: nil, char: _char, rules: _rules) do
nil
@jwhiteman
jwhiteman / client.rb
Last active January 7, 2017 07:45
UDP in Ruby - packing socket manually
# or `echo some-request | nc localhost 8181 -4u `
MAX_READ = 1024 * 8
FLAGS = 0
c = Socket.new :INET, :DGRAM
s = Socket.pack_sockaddr_in 8181, "127.0.0.1"
c.send("some-request", FLAGS, s)
res = c.recv(MAX_READ)
@jwhiteman
jwhiteman / strace.sh
Created December 30, 2016 18:33
sort strace output
strace cmd 2> /dev/stdout | cut -d '(' -f 1 | sort | uniq | grep -v "[+=]" | sort -rn -k1,1
@jwhiteman
jwhiteman / join.rb
Created November 19, 2016 19:22
Thread#join
# A reminder that join conceptually combines the stacks of the parent and child threads.
# If you consider that the stack grows downard, the child stack will sit below the parent
# stack. See output below.
def main?
Thread.current == Thread.main
end
def name
if main?
"main"
@jwhiteman
jwhiteman / pipe.rb
Created November 18, 2016 07:55
Simple pipeline using Threads and Queues
require "thread"
stage_one = Queue.new
stage_two = Queue.new
stage_three = Queue.new
stage_one_worker = Thread.new do
100.times do |n|
stage_one << n