iffy/index.html

## index.html
<html>
    <head>
        <title>Bite-sized Twisted: Introduction and the Reactor</title>
        <style>
        body {
font: normal normal 16px Crimson Text;
color: #666666;
background: #ffffff none repeat scroll top left;
padding: 0 0 0 0;
}
html body .region-inner {
min-width: 0;
max-width: 100%;
width: auto;
}
a:link {
text-decoration:underline;
color: #2288bb;
}
a:visited {
text-decoration:underline;
color: #888888;
}
a:hover {
text-decoration:underline;
color: #33aaff;
}
.body-fauxcolumn-outer .fauxcolumn-inner {
background: transparent none repeat scroll top left;
_background-image: none;
}
.body-fauxcolumn-outer .cap-top {
position: absolute;
z-index: 1;
height: 400px;
width: 100%;
background: #ffffff none repeat scroll top left;
}
.body-fauxcolumn-outer .cap-top .cap-left {
width: 100%;
background: transparent none repeat-x scroll top left;
_background-image: none;
}
.content-outer {
-moz-box-shadow: 0 0 0 rgba(0, 0, 0, .15);
-webkit-box-shadow: 0 0 0 rgba(0, 0, 0, .15);
-goog-ms-box-shadow: 0 0 0 #333333;
box-shadow: 0 0 0 rgba(0, 0, 0, .15);
margin-bottom: 1px;
}
.content-inner {
padding: 10px 40px;
}
.content-inner {
background-color: #ffffff;
}
/* Header
----------------------------------------------- */
.header-outer {
background: transparent none repeat-x scroll 0 -400px;
_background-image: none;
}
.Header h1 {
font: normal normal 60px Crimson Text;
color: #999999;
text-shadow: 0 0 0 rgba(0, 0, 0, .2);
}
.Header h1 a {
color: #999999;
}
.Header .description {
font-size: 18px;
color: #000000;
}
.header-inner .Header .titlewrapper {
padding: 22px 0;
}
.header-inner .Header .descriptionwrapper {
padding: 0 0;
}
/* Tabs
----------------------------------------------- */
.tabs-inner .section:first-child {
border-top: 0 solid #dddddd;
}
.tabs-inner .section:first-child ul {
margin-top: -1px;
border-top: 1px solid #dddddd;
border-left: 1px solid #dddddd;
border-right: 1px solid #dddddd;
}
.tabs-inner .widget ul {
background: transparent none repeat-x scroll 0 -800px;
_background-image: none;
border-bottom: 1px solid #dddddd;
margin-top: 0;
margin-left: -30px;
margin-right: -30px;
}
.tabs-inner .widget li a {
display: inline-block;
padding: .6em 1em;
font: normal normal 14px Crimson Text;
color: #000000;
border-left: 1px solid #ffffff;
border-right: 1px solid #dddddd;
}
.tabs-inner .widget li:first-child a {
border-left: none;
}
.tabs-inner .widget li.selected a, .tabs-inner .widget li a:hover {
color: #000000;
background-color: #eeeeee;
text-decoration: none;
}
/* Columns
----------------------------------------------- */
.main-outer {
border-top: 0 solid transparent;
}
.fauxcolumn-left-outer .fauxcolumn-inner {
border-right: 1px solid transparent;
}
.fauxcolumn-right-outer .fauxcolumn-inner {
border-left: 1px solid transparent;
}
/* Headings
----------------------------------------------- */
h2 {
margin: 2em 0 1em 0;
font: normal normal 16px Crimson Text;
color: #000000;
text-transform: uppercase;
}
/* Widgets
----------------------------------------------- */
.widget .zippy {
color: #999999;
text-shadow: 2px 2px 1px rgba(0, 0, 0, .1);
}
.widget .popular-posts ul {
list-style: none;
}
/* Posts
----------------------------------------------- */
.date-header span {
background-color: #bbbbbb;
color: #ffffff;
padding: 0.4em;
letter-spacing: 3px;
margin: inherit;
}
.main-inner {
padding-top: 35px;
padding-bottom: 65px;
}
.main-inner .column-center-inner {
padding: 0 0;
}
.main-inner .column-center-inner .section {
margin: 0 1em;
}
.post {
margin: 0 0 45px 0;
}
h3.post-title, .comments h4 {
font: normal normal 22px Crimson Text;
margin: .75em 0 0;
}
.post-body {
font-size: 110%;
line-height: 1.4;
position: relative;
}
.post-body img, .post-body .tr-caption-container, .Profile img, .Image img,
.BlogList .item-thumbnail img {
padding: 2px;
background: #ffffff;
border: 1px solid #eeeeee;
-moz-box-shadow: 1px 1px 5px rgba(0, 0, 0, .1);
-webkit-box-shadow: 1px 1px 5px rgba(0, 0, 0, .1);
box-shadow: 1px 1px 5px rgba(0, 0, 0, .1);
}
.post-body img, .post-body .tr-caption-container {
padding: 5px;
}
.post-body .tr-caption-container {
color: #666666;
}
.post-body .tr-caption-container img {
padding: 0;
background: transparent;
border: none;
-moz-box-shadow: 0 0 0 rgba(0, 0, 0, .1);
-webkit-box-shadow: 0 0 0 rgba(0, 0, 0, .1);
box-shadow: 0 0 0 rgba(0, 0, 0, .1);
}
.post-header {
margin: 0 0 1.5em;
line-height: 1.6;
font-size: 90%;
}
.post-footer {
margin: 20px -2px 0;
padding: 5px 10px;
color: #666666;
background-color: #eeeeee;
border-bottom: 1px solid #eeeeee;
line-height: 1.6;
font-size: 90%;
}
#comments .comment-author {
padding-top: 1.5em;
border-top: 1px solid transparent;
background-position: 0 1.5em;
}
#comments .comment-author:first-child {
padding-top: 0;
border-top: none;
}
.avatar-image-container {
margin: .2em 0 0;
}
#comments .avatar-image-container img {
border: 1px solid #eeeeee;
}
/* Comments
----------------------------------------------- */
.comments .comments-content .icon.blog-author {
background-repeat: no-repeat;
background-image: url(data:image/png;base64,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);
}
.comments .comments-content .loadmore a {
border-top: 1px solid #999999;
border-bottom: 1px solid #999999;
}
.comments .comment-thread.inline-thread {
background-color: #eeeeee;
}
.comments .continue {
border-top: 2px solid #999999;
}
/* Accents
---------------------------------------------- */
.section-columns td.columns-cell {
border-left: 1px solid transparent;
}
.blog-pager {
background: transparent url(http://www.blogblog.com/1kt/simple/paging_dot.png) repeat-x scroll top center;
}
.blog-pager-older-link, .home-link,
.blog-pager-newer-link {
background-color: #ffffff;
padding: 5px;
}
.footer-outer {
border-top: 1px dashed #bbbbbb;
}
/* Mobile
----------------------------------------------- */
body.mobile  {
background-size: auto;
}
.mobile .body-fauxcolumn-outer {
background: transparent none repeat scroll top left;
}
.mobile .body-fauxcolumn-outer .cap-top {
background-size: 100% auto;
}
.mobile .content-outer {
-webkit-box-shadow: 0 0 3px rgba(0, 0, 0, .15);
box-shadow: 0 0 3px rgba(0, 0, 0, .15);
padding: 0 0;
}
body.mobile .AdSense {
margin: 0 -0;
}
.mobile .tabs-inner .widget ul {
margin-left: 0;
margin-right: 0;
}
.mobile .post {
margin: 0;
}
.mobile .main-inner .column-center-inner .section {
margin: 0;
}
.mobile .date-header span {
padding: 0.1em 10px;
margin: 0 -10px;
}
.mobile h3.post-title {
margin: 0;
}
.mobile .blog-pager {
background: transparent none no-repeat scroll top center;
}
.mobile .footer-outer {
border-top: none;
}
.mobile .main-inner, .mobile .footer-inner {
background-color: #ffffff;
}
.mobile-index-contents {
color: #666666;
}
.mobile-link-button {
background-color: #2288bb;
}
.mobile-link-button a:link, .mobile-link-button a:visited {
color: #ffffff;
}
.mobile .tabs-inner .section:first-child {
border-top: none;
}
.mobile .tabs-inner .PageList .widget-content {
background-color: #eeeeee;
color: #000000;
border-top: 1px solid #dddddd;
border-bottom: 1px solid #dddddd;
}
.mobile .tabs-inner .PageList .widget-content .pagelist-arrow {
border-left: 1px solid #dddddd;
}
        div.code {
background: #eee;
border: 1px solid steelblue;
border-width: 1px 0px 1px;
padding-right: 12px;
padding-left: 12px;
}
ul.hierarchy li {
padding-left: 0em !important;
}
h1.title {
padding-left: 16px;
}
footer {
display: none;
}
#navbar {
background: #999;
opacity: 0 !important;
}
#navbar:hover {
opacity: 1.0 !important;
transition: opacity 1s;
-moz-transition: opacity 1s;
-webkit-transition: opacity 1s;
-o-transition: opacity 1s;
}
h1.title {
font-size: 66px;
}
h3.post-title {
font-size: 40px;
}
h2 {
text-transform: none;
font-size: 24px
}
div.date-outer {
margin-bottom: 12em;
}
.code .hll { background-color: #ffffcc }
.code  { background: #f8f8f8; }
.code .c { color: #408080; font-style: italic } /* Comment */
.code .err { border: 1px solid #FF0000 } /* Error */
.code .k { color: #008000; font-weight: bold } /* Keyword */
.code .o { color: #666666 } /* Operator */
.code .cm { color: #408080; font-style: italic } /* Comment.Multiline */
.code .cp { color: #BC7A00 } /* Comment.Preproc */
.code .c1 { color: #408080; font-style: italic } /* Comment.Single */
.code .cs { color: #408080; font-style: italic } /* Comment.Special */
.code .gd { color: #A00000 } /* Generic.Deleted */
.code .ge { font-style: italic } /* Generic.Emph */
.code .gr { color: #FF0000 } /* Generic.Error */
.code .gh { color: #000080; font-weight: bold } /* Generic.Heading */
.code .gi { color: #00A000 } /* Generic.Inserted */
.code .go { color: #808080 } /* Generic.Output */
.code .gp { color: #000080; font-weight: bold } /* Generic.Prompt */
.code .gs { font-weight: bold } /* Generic.Strong */
.code .gu { color: #800080; font-weight: bold } /* Generic.Subheading */
.code .gt { color: #0040D0 } /* Generic.Traceback */
.code .kc { color: #008000; font-weight: bold } /* Keyword.Constant */
.code .kd { color: #008000; font-weight: bold } /* Keyword.Declaration */
.code .kn { color: #008000; font-weight: bold } /* Keyword.Namespace */
.code .kp { color: #008000 } /* Keyword.Pseudo */
.code .kr { color: #008000; font-weight: bold } /* Keyword.Reserved */
.code .kt { color: #B00040 } /* Keyword.Type */
.code .m { color: #666666 } /* Literal.Number */
.code .s { color: #BA2121 } /* Literal.String */
.code .na { color: #7D9029 } /* Name.Attribute */
.code .nb { color: #008000 } /* Name.Builtin */
.code .nc { color: #0000FF; font-weight: bold } /* Name.Class */
.code .no { color: #880000 } /* Name.Constant */
.code .nd { color: #AA22FF } /* Name.Decorator */
.code .ni { color: #999999; font-weight: bold } /* Name.Entity */
.code .ne { color: #D2413A; font-weight: bold } /* Name.Exception */
.code .nf { color: #0000FF } /* Name.Function */
.code .nl { color: #A0A000 } /* Name.Label */
.code .nn { color: #0000FF; font-weight: bold } /* Name.Namespace */
.code .nt { color: #008000; font-weight: bold } /* Name.Tag */
.code .nv { color: #19177C } /* Name.Variable */
.code .ow { color: #AA22FF; font-weight: bold } /* Operator.Word */
.code .w { color: #bbbbbb } /* Text.Whitespace */
.code .mf { color: #666666 } /* Literal.Number.Float */
.code .mh { color: #666666 } /* Literal.Number.Hex */
.code .mi { color: #666666 } /* Literal.Number.Integer */
.code .mo { color: #666666 } /* Literal.Number.Oct */
.code .sb { color: #BA2121 } /* Literal.String.Backtick */
.code .sc { color: #BA2121 } /* Literal.String.Char */
.code .sd { color: #BA2121; font-style: italic } /* Literal.String.Doc */
.code .s2 { color: #BA2121 } /* Literal.String.Double */
.code .se { color: #BB6622; font-weight: bold } /* Literal.String.Escape */
.code .sh { color: #BA2121 } /* Literal.String.Heredoc */
.code .si { color: #BB6688; font-weight: bold } /* Literal.String.Interpol */
.code .sx { color: #008000 } /* Literal.String.Other */
.code .sr { color: #BB6688 } /* Literal.String.Regex */
.code .s1 { color: #BA2121 } /* Literal.String.Single */
.code .ss { color: #19177C } /* Literal.String.Symbol */
.code .bp { color: #008000 } /* Name.Builtin.Pseudo */
.code .vc { color: #19177C } /* Name.Variable.Class */
.code .vg { color: #19177C } /* Name.Variable.Global */
.code .vi { color: #19177C } /* Name.Variable.Instance */
.code .il { color: #666666 } /* Literal.Number.Integer.Long */
.python .hll { background-color: #ffffcc }
.python  { background: #f8f8f8; }
.python .c { color: #408080; font-style: italic } /* Comment */
.python .err { border: 1px solid #FF0000 } /* Error */
.python .k { color: #008000; font-weight: bold } /* Keyword */
.python .o { color: #666666 } /* Operator */
.python .cm { color: #408080; font-style: italic } /* Comment.Multiline */
.python .cp { color: #BC7A00 } /* Comment.Preproc */
.python .c1 { color: #408080; font-style: italic } /* Comment.Single */
.python .cs { color: #408080; font-style: italic } /* Comment.Special */
.python .gd { color: #A00000 } /* Generic.Deleted */
.python .ge { font-style: italic } /* Generic.Emph */
.python .gr { color: #FF0000 } /* Generic.Error */
.python .gh { color: #000080; font-weight: bold } /* Generic.Heading */
.python .gi { color: #00A000 } /* Generic.Inserted */
.python .go { color: #808080 } /* Generic.Output */
.python .gp { color: #000080; font-weight: bold } /* Generic.Prompt */
.python .gs { font-weight: bold } /* Generic.Strong */
.python .gu { color: #800080; font-weight: bold } /* Generic.Subheading */
.python .gt { color: #0040D0 } /* Generic.Traceback */
.python .kc { color: #008000; font-weight: bold } /* Keyword.Constant */
.python .kd { color: #008000; font-weight: bold } /* Keyword.Declaration */
.python .kn { color: #008000; font-weight: bold } /* Keyword.Namespace */
.python .kp { color: #008000 } /* Keyword.Pseudo */
.python .kr { color: #008000; font-weight: bold } /* Keyword.Reserved */
.python .kt { color: #B00040 } /* Keyword.Type */
.python .m { color: #666666 } /* Literal.Number */
.python .s { color: #BA2121 } /* Literal.String */
.python .na { color: #7D9029 } /* Name.Attribute */
.python .nb { color: #008000 } /* Name.Builtin */
.python .nc { color: #0000FF; font-weight: bold } /* Name.Class */
.python .no { color: #880000 } /* Name.Constant */
.python .nd { color: #AA22FF } /* Name.Decorator */
.python .ni { color: #999999; font-weight: bold } /* Name.Entity */
.python .ne { color: #D2413A; font-weight: bold } /* Name.Exception */
.python .nf { color: #0000FF } /* Name.Function */
.python .nl { color: #A0A000 } /* Name.Label */
.python .nn { color: #0000FF; font-weight: bold } /* Name.Namespace */
.python .nt { color: #008000; font-weight: bold } /* Name.Tag */
.python .nv { color: #19177C } /* Name.Variable */
.python .ow { color: #AA22FF; font-weight: bold } /* Operator.Word */
.python .w { color: #bbbbbb } /* Text.Whitespace */
.python .mf { color: #666666 } /* Literal.Number.Float */
.python .mh { color: #666666 } /* Literal.Number.Hex */
.python .mi { color: #666666 } /* Literal.Number.Integer */
.python .mo { color: #666666 } /* Literal.Number.Oct */
.python .sb { color: #BA2121 } /* Literal.String.Backtick */
.python .sc { color: #BA2121 } /* Literal.String.Char */
.python .sd { color: #BA2121; font-style: italic } /* Literal.String.Doc */
.python .s2 { color: #BA2121 } /* Literal.String.Double */
.python .se { color: #BB6622; font-weight: bold } /* Literal.String.Escape */
.python .sh { color: #BA2121 } /* Literal.String.Heredoc */
.python .si { color: #BB6688; font-weight: bold } /* Literal.String.Interpol */
.python .sx { color: #008000 } /* Literal.String.Other */
.python .sr { color: #BB6688 } /* Literal.String.Regex */
.python .s1 { color: #BA2121 } /* Literal.String.Single */
.python .ss { color: #19177C } /* Literal.String.Symbol */
.python .bp { color: #008000 } /* Name.Builtin.Pseudo */
.python .vc { color: #19177C } /* Name.Variable.Class */
.python .vg { color: #19177C } /* Name.Variable.Global */
.python .vi { color: #19177C } /* Name.Variable.Instance */
.python .il { color: #666666 } /* Literal.Number.Integer.Long */
.javascript .hll { background-color: #ffffcc }
.javascript  { background: #f8f8f8; }
.javascript .c { color: #408080; font-style: italic } /* Comment */
.javascript .err { border: 1px solid #FF0000 } /* Error */
.javascript .k { color: #008000; font-weight: bold } /* Keyword */
.javascript .o { color: #666666 } /* Operator */
.javascript .cm { color: #408080; font-style: italic } /* Comment.Multiline */
.javascript .cp { color: #BC7A00 } /* Comment.Preproc */
.javascript .c1 { color: #408080; font-style: italic } /* Comment.Single */
.javascript .cs { color: #408080; font-style: italic } /* Comment.Special */
.javascript .gd { color: #A00000 } /* Generic.Deleted */
.javascript .ge { font-style: italic } /* Generic.Emph */
.javascript .gr { color: #FF0000 } /* Generic.Error */
.javascript .gh { color: #000080; font-weight: bold } /* Generic.Heading */
.javascript .gi { color: #00A000 } /* Generic.Inserted */
.javascript .go { color: #808080 } /* Generic.Output */
.javascript .gp { color: #000080; font-weight: bold } /* Generic.Prompt */
.javascript .gs { font-weight: bold } /* Generic.Strong */
.javascript .gu { color: #800080; font-weight: bold } /* Generic.Subheading */
.javascript .gt { color: #0040D0 } /* Generic.Traceback */
.javascript .kc { color: #008000; font-weight: bold } /* Keyword.Constant */
.javascript .kd { color: #008000; font-weight: bold } /* Keyword.Declaration */
.javascript .kn { color: #008000; font-weight: bold } /* Keyword.Namespace */
.javascript .kp { color: #008000 } /* Keyword.Pseudo */
.javascript .kr { color: #008000; font-weight: bold } /* Keyword.Reserved */
.javascript .kt { color: #B00040 } /* Keyword.Type */
.javascript .m { color: #666666 } /* Literal.Number */
.javascript .s { color: #BA2121 } /* Literal.String */
.javascript .na { color: #7D9029 } /* Name.Attribute */
.javascript .nb { color: #008000 } /* Name.Builtin */
.javascript .nc { color: #0000FF; font-weight: bold } /* Name.Class */
.javascript .no { color: #880000 } /* Name.Constant */
.javascript .nd { color: #AA22FF } /* Name.Decorator */
.javascript .ni { color: #999999; font-weight: bold } /* Name.Entity */
.javascript .ne { color: #D2413A; font-weight: bold } /* Name.Exception */
.javascript .nf { color: #0000FF } /* Name.Function */
.javascript .nl { color: #A0A000 } /* Name.Label */
.javascript .nn { color: #0000FF; font-weight: bold } /* Name.Namespace */
.javascript .nt { color: #008000; font-weight: bold } /* Name.Tag */
.javascript .nv { color: #19177C } /* Name.Variable */
.javascript .ow { color: #AA22FF; font-weight: bold } /* Operator.Word */
.javascript .w { color: #bbbbbb } /* Text.Whitespace */
.javascript .mf { color: #666666 } /* Literal.Number.Float */
.javascript .mh { color: #666666 } /* Literal.Number.Hex */
.javascript .mi { color: #666666 } /* Literal.Number.Integer */
.javascript .mo { color: #666666 } /* Literal.Number.Oct */
.javascript .sb { color: #BA2121 } /* Literal.String.Backtick */
.javascript .sc { color: #BA2121 } /* Literal.String.Char */
.javascript .sd { color: #BA2121; font-style: italic } /* Literal.String.Doc */
.javascript .s2 { color: #BA2121 } /* Literal.String.Double */
.javascript .se { color: #BB6622; font-weight: bold } /* Literal.String.Escape */
.javascript .sh { color: #BA2121 } /* Literal.String.Heredoc */
.javascript .si { color: #BB6688; font-weight: bold } /* Literal.String.Interpol */
.javascript .sx { color: #008000 } /* Literal.String.Other */
.javascript .sr { color: #BB6688 } /* Literal.String.Regex */
.javascript .s1 { color: #BA2121 } /* Literal.String.Single */
.javascript .ss { color: #19177C } /* Literal.String.Symbol */
.javascript .bp { color: #008000 } /* Name.Builtin.Pseudo */
.javascript .vc { color: #19177C } /* Name.Variable.Class */
.javascript .vg { color: #19177C } /* Name.Variable.Global */
.javascript .vi { color: #19177C } /* Name.Variable.Instance */
.javascript .il { color: #666666 } /* Literal.Number.Integer.Long */

.caption {
    font-style: italic;
    text-align: right;
    position: relative;
    top: -1.3em;
    right: 5px;
    opacity: 0.75;
}
        </style>
    </head>
    <body>
        <div style="width: 800px;">
        <h2>Why I'm writing this</h2><p><a href="http://twistedmatrix.com/">Twisted</a> has enabled me to do some amazing things -- things I hadn't thought possible.  Others haven't had the same delightful experience.  Their descriptions of Twisted include less glowing adjectives.  My intent with this and related posts is to ameliorate some of those adjectives.</p><p>I'm borrowing conceptually from JP Calderone's excellent <a href="http://twistedmatrix.com/documents/current/web/howto/web-in-60/index.html">Twisted Web in 60 Seconds</a> series by keeping these posts relatively short.  Also, there's <a href="http://krondo.com/?page_id=1327">KRONDO blog's Twisted Introduction</a>, another great series for learning Twisted (and general Asynchronous Programming).</p><h2>Bomberman</h2><p>Bomberman is great!  So, let's make it.  By the end (or maybe somewhere in the middle) of these Bite-sized Twisted posts, I'm hoping that some semblance of a Bomberman clone emerges.  That's the goal, at least.</p><p>Also, am I the only one who thought Super Smash Bros should have included Bomberman?  And MegaMan?</p><h2>The Reactor</h2><p>The reactor is central to Twisted.  You may not always interact with it directly, but it'll almost always be there, reacting away.  To start the reactor, call its <code>run</code> method:</p><div class="code python"><pre><span class="kn">from</span> <span class="nn">twisted.internet</span> <span class="kn">import</span> <span class="n">reactor</span><br /><span class="n">reactor</span><span class="o">.</span><span class="n">run</span><span class="p">()</span><br /></pre></div><div class="caption">snippet1.py</div><p>Run this code and you'll see it hang:</p><div class="code bash"><pre><br /></pre></div><h2>Nothing != Something</h2><p>You might be tempted to say, "nothing happened."  Don't say that.  <i>Something</i> happened; in fact it's still happening, and will continue to happen until you stop it (press <code>Control-C</code>).  The <i>something</i> happening is the reactor running.  To prove it, run this code:</p><div class="code python"><pre><span class="kn">from</span> <span class="nn">twisted.internet</span> <span class="kn">import</span> <span class="n">reactor</span><br /><span class="k">print</span> <span class="s">&#39;Hello,&#39;</span><br /><span class="n">reactor</span><span class="o">.</span><span class="n">run</span><span class="p">()</span><br /><span class="k">print</span> <span class="s">&#39;world!&#39;</span><br /></pre></div><div class="caption">snippet2.py</div><p>You should see the <code>Hello,</code> but won't see the <code>world!</code> until you stop the reactor:</p><div class="code text"><pre>Hello,<br />^Cworld!<br /></pre></div><p>(The <code>^C</code> is what my terminal prints when I press <code>Control-C</code>)</p><h2>What does the reactor do?</h2><p>The reactor reacts to events.  One kind of event it can react to is the passage of time (scheduled events):</p><div class="code python"><pre><span class="kn">from</span> <span class="nn">twisted.internet</span> <span class="kn">import</span> <span class="n">reactor</span><br /><span class="n">reactor</span><span class="o">.</span><span class="n">callLater</span><span class="p">(</span><span class="mi">2</span><span class="p">,</span> <span class="n">reactor</span><span class="o">.</span><span class="n">stop</span><span class="p">)</span><br /><span class="n">reactor</span><span class="o">.</span><span class="n">run</span><span class="p">()</span><br /></pre></div><div class="caption">snippet3.py</div><p><i>snippet3.py</i> tells the reactor to call <code>reactor.stop</code> after 2 seconds, then it starts the reactor with <code>reactor.run()</code>.  After 2 seconds, <code>reactor.stop</code> is called, stopping the reactor, and the process exits.</p><p>The first argument to <code>reactor.callLater</code> is the number of seconds to wait before calling the function.  The second argument is the function to call.  It's important that it's <code>reactor.stop</code>, <b>not</b> <code>reactor.stop()</code>.  <code>reactor.callLater</code> expects the reference to the function, not the result of the function.  Passing function references is a common idiom in the Twisted API.</p><p>Also, you can <a href="http://twistedmatrix.com/documents/current/api/twisted.internet.base.ReactorBase.html#callLater">read the <code>callLater</code> docs for yourself.</a>  (See twisted.internet.interfaces.IReactorTime.callLater as it says)</p><h2>Make a bomb</h2><p>If we're going to make Bomberman, we'll need bombs.  Bombs have fuses.  Let's light some fuses:</p><div class="code python"><pre><span class="kn">from</span> <span class="nn">twisted.internet</span> <span class="kn">import</span> <span class="n">reactor</span><br /><br /><span class="k">def</span> <span class="nf">explode</span><span class="p">(</span><span class="n">message</span><span class="p">):</span><br />    <span class="k">print</span> <span class="s">&#39;BOOM! &#39;</span> <span class="o">+</span> <span class="n">message</span><br /><br /><span class="n">reactor</span><span class="o">.</span><span class="n">callLater</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="n">explode</span><span class="p">,</span> <span class="s">&#39;first one&#39;</span><span class="p">)</span><br /><span class="n">reactor</span><span class="o">.</span><span class="n">callLater</span><span class="p">(</span><span class="mi">2</span><span class="p">,</span> <span class="n">explode</span><span class="p">,</span> <span class="s">&#39;second one&#39;</span><span class="p">)</span><br /><span class="n">reactor</span><span class="o">.</span><span class="n">callLater</span><span class="p">(</span><span class="mi">3</span><span class="p">,</span> <span class="n">reactor</span><span class="o">.</span><span class="n">stop</span><span class="p">)</span><br /><span class="n">reactor</span><span class="o">.</span><span class="n">run</span><span class="p">()</span><br /></pre></div><div class="caption">bomb.py</div><p>Run it.  After 1 second, the first bomb explodes.  After 1 more second, the second explodes.  After 1 more, the process exits:</p><div class="code text"><pre>BOOM! first one<br />BOOM! second one<br /></pre></div><p>In <i>bomb.py</i>, note two things:</p><p>First, when scheduling <code>explode</code> we also pass a string (<code>'first one'</code>) as an extra argument to <code>reactor.callLater</code>.  This argument is eventually passed to <code>explode</code> as it's first argument.  <code>callLater</code> takes any number of arguments and keyword arguments, which it will use to call the scheduled method.</p><p>Second, do the explosions happen when you expect them to?  Consider this synchronous code, which has the same timed output as <i>bomb.py</i>:</p><div class="code python"><pre><span class="kn">import</span> <span class="nn">time</span><br /><br /><span class="k">def</span> <span class="nf">explode</span><span class="p">(</span><span class="n">message</span><span class="p">):</span><br />    <span class="k">print</span> <span class="s">&#39;BOOM! &#39;</span> <span class="o">+</span> <span class="n">message</span><br /><br /><span class="n">time</span><span class="o">.</span><span class="n">sleep</span><span class="p">(</span><span class="mi">1</span><span class="p">)</span><br /><span class="n">explode</span><span class="p">(</span><span class="s">&#39;first one&#39;</span><span class="p">)</span><br /><span class="n">time</span><span class="o">.</span><span class="n">sleep</span><span class="p">(</span><span class="mi">1</span><span class="p">)</span><br /><span class="n">explode</span><span class="p">(</span><span class="s">&#39;second one&#39;</span><span class="p">)</span><br /><span class="n">time</span><span class="o">.</span><span class="n">sleep</span><span class="p">(</span><span class="mi">1</span><span class="p">)</span><br /></pre></div><div class="caption">synchronous.py</div><p>In the synchronous code, since commands happen sequentially, you specify the timing offset from one command to the other.  In the asynchronous code, scheduled commands are independent of each other: you specify the timing offset from the time that you schedule the command.</p><p><i>synchronous.py</i> has the same output as <i>bomb.py</i>, <b>but it does not do the same thing.</b>  This will become more apparent when we start adding input/output to programs.</p>
        </div>
    </body>
</html>