<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<title>Mu - 065duplex_list.mu</title>
<meta name="Generator" content="Vim/7.4">
<meta name="plugin-version" content="vim7.4_v1">
<meta name="syntax" content="none">
<meta name="settings" content="use_css,pre_wrap,no_foldcolumn,expand_tabs,prevent_copy=">
<meta name="colorscheme" content="minimal">
<style type="text/css">
<!--
pre { white-space: pre-wrap; font-family: monospace; color: #eeeeee; background-color: #080808; }
body { font-family: monospace; color: #eeeeee; background-color: #080808; }
* { font-size: 1.05em; }
.muControl { color: #c0a020; }
.muRecipe { color: #ff8700; }
.muScenario { color: #00af00; }
.CommentedCode { color: #6c6c6c; }
.Comment { color: #9090ff; }
.Constant { color: #00a0a0; }
.Special { color: #ff6060; }
.Delimiter { color: #a04060; }
-->
</style>
<script type='text/javascript'>
<!--
-->
</script>
</head>
<body>
<pre id='vimCodeElement'>
<span class="Comment"># A doubly linked list permits bidirectional traversal.</span>
container duplex-list [
value:location
next:address:duplex-list
prev:address:duplex-list
]
<span class="Comment"># result:address:duplex-list <- push-duplex x:location, in:address:duplex-list</span>
<span class="muRecipe">recipe</span> push-duplex [
<span class="Constant">local-scope</span>
x:location<span class="Special"> <- </span><span class="Constant">next-ingredient</span>
in:address:duplex-list<span class="Special"> <- </span><span class="Constant">next-ingredient</span>
result:address:duplex-list<span class="Special"> <- </span>new <span class="Constant">duplex-list:type</span>
val:address:location<span class="Special"> <- </span>get-address *result, <span class="Constant">value:offset</span>
*val<span class="Special"> <- </span>copy x
next:address:address:duplex-list<span class="Special"> <- </span>get-address *result, <span class="Constant">next:offset</span>
*next<span class="Special"> <- </span>copy in
<span class="muControl">reply-unless</span> in, result
prev:address:address:duplex-list<span class="Special"> <- </span>get-address *in, <span class="Constant">prev:offset</span>
*prev<span class="Special"> <- </span>copy result
<span class="muControl">reply</span> result
]
<span class="Comment"># result:location <- first-duplex in:address:duplex-list</span>
<span class="muRecipe">recipe</span> first-duplex [
<span class="Constant">local-scope</span>
in:address:duplex-list<span class="Special"> <- </span><span class="Constant">next-ingredient</span>
<span class="muControl">reply-unless</span> in, <span class="Constant">0</span>
result:location<span class="Special"> <- </span>get *in, <span class="Constant">value:offset</span>
<span class="muControl">reply</span> result
]
<span class="Comment"># result:address:duplex-list <- next-duplex in:address:duplex-list</span>
<span class="muRecipe">recipe</span> next-duplex [
<span class="Constant">local-scope</span>
in:address:duplex-list<span class="Special"> <- </span><span class="Constant">next-ingredient</span>
<span class="muControl">reply-unless</span> in, <span class="Constant">0</span>
result:address:duplex-list<span class="Special"> <- </span>get *in, <span class="Constant">next:offset</span>
<span class="muControl">reply</span> result
]
<span class="Comment"># result:address:duplex-list <- prev-duplex in:address:duplex-list</span>
<span class="muRecipe">recipe</span> prev-duplex [
<span class="Constant">local-scope</span>
in:address:duplex-list<span class="Special"> <- </span><span class="Constant">next-ingredient</span>
<span class="muControl">reply-unless</span> in, <span class="Constant">0</span>
result:address:duplex-list<span class="Special"> <- </span>get *in, <span class="Constant">prev:offset</span>
<span class="muControl">reply</span> result
]
<span class="muScenario">scenario</span> duplex-list-handling [
run [
<span class="Comment"># reserve locations 0, 1 and 2 to check for missing null check</span>
<span class="Constant">1</span>:number<span class="Special"> <- </span>copy <span class="Constant">34</span>
<span class="Constant">2</span>:number<span class="Special"> <- </span>copy <span class="Constant">35</span>
<span class="Constant">3</span>:address:duplex-list<span class="Special"> <- </span>copy <span class="Constant">0</span>
<span class="Constant">3</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">3</span>, <span class="Constant">3</span>:address:duplex-list
<span class="Constant">3</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">4</span>, <span class="Constant">3</span>:address:duplex-list
<span class="Constant">3</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">5</span>, <span class="Constant">3</span>:address:duplex-list
<span class="Constant">4</span>:address:duplex-list<span class="Special"> <- </span>copy <span class="Constant">3</span>:address:duplex-list
<span class="Constant">5</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">4</span>:address:duplex-list
<span class="Constant">4</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">4</span>:address:duplex-list
<span class="Constant">6</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">4</span>:address:duplex-list
<span class="Constant">4</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">4</span>:address:duplex-list
<span class="Constant">7</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">4</span>:address:duplex-list
<span class="Constant">8</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">4</span>:address:duplex-list
<span class="Constant">9</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">8</span>:address:duplex-list
<span class="Constant">10</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">8</span>:address:duplex-list
<span class="Constant">11</span>:address:duplex-list<span class="Special"> <- </span>prev-duplex <span class="Constant">8</span>:address:duplex-list
<span class="Constant">4</span>:address:duplex-list<span class="Special"> <- </span>prev-duplex <span class="Constant">4</span>:address:duplex-list
<span class="Constant">12</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">4</span>:address:duplex-list
<span class="Constant">4</span>:address:duplex-list<span class="Special"> <- </span>prev-duplex <span class="Constant">4</span>:address:duplex-list
<span class="Constant">13</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">4</span>:address:duplex-list
<span class="Constant">14</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">3</span>:address:duplex-list, <span class="Constant">4</span>:address:duplex-list
<span class="CommentedCode">#? $dump-trace #? 1</span>
]
memory-should-contain [
<span class="Constant">0</span><span class="Special"> <- </span><span class="Constant">0</span> <span class="Comment"># no modifications to null pointers</span>
<span class="Constant">1</span><span class="Special"> <- </span><span class="Constant">34</span>
<span class="Constant">2</span><span class="Special"> <- </span><span class="Constant">35</span>
<span class="Constant">5</span><span class="Special"> <- </span><span class="Constant">5</span> <span class="Comment"># scanning next</span>
<span class="Constant">6</span><span class="Special"> <- </span><span class="Constant">4</span>
<span class="Constant">7</span><span class="Special"> <- </span><span class="Constant">3</span>
<span class="Constant">8</span><span class="Special"> <- </span><span class="Constant">0</span> <span class="Comment"># null</span>
<span class="Constant">9</span><span class="Special"> <- </span><span class="Constant">0</span> <span class="Comment"># first of null</span>
<span class="Constant">10</span><span class="Special"> <- </span><span class="Constant">0</span> <span class="Comment"># next of null</span>
<span class="Constant">11</span><span class="Special"> <- </span><span class="Constant">0</span> <span class="Comment"># prev of null</span>
<span class="Constant">12</span><span class="Special"> <- </span><span class="Constant">4</span> <span class="Comment"># then start scanning prev</span>
<span class="Constant">13</span><span class="Special"> <- </span><span class="Constant">5</span>
<span class="Constant">14</span><span class="Special"> <- </span><span class="Constant">1</span> <span class="Comment"># list back at start</span>
]
]
<span class="Comment"># l:address:duplex-list <- insert-duplex x:location, in:address:duplex-list</span>
<span class="Comment"># Inserts 'x' after 'in'. Returns some pointer into the list.</span>
<span class="muRecipe">recipe</span> insert-duplex [
<span class="Constant">local-scope</span>
x:location<span class="Special"> <- </span><span class="Constant">next-ingredient</span>
in:address:duplex-list<span class="Special"> <- </span><span class="Constant">next-ingredient</span>
new-node:address:duplex-list<span class="Special"> <- </span>new <span class="Constant">duplex-list:type</span>
val:address:location<span class="Special"> <- </span>get-address *new-node, <span class="Constant">value:offset</span>
*val<span class="Special"> <- </span>copy x
next-node:address:duplex-list<span class="Special"> <- </span>get *in, <span class="Constant">next:offset</span>
<span class="Comment"># in.next = new-node</span>
y:address:address:duplex-list<span class="Special"> <- </span>get-address *in, <span class="Constant">next:offset</span>
*y<span class="Special"> <- </span>copy new-node
<span class="Comment"># new-node.prev = in</span>
y<span class="Special"> <- </span>get-address *new-node, <span class="Constant">prev:offset</span>
*y<span class="Special"> <- </span>copy in
<span class="Comment"># new-node.next = next-node</span>
y<span class="Special"> <- </span>get-address *new-node, <span class="Constant">next:offset</span>
*y<span class="Special"> <- </span>copy next-node
<span class="Comment"># if next-node is not null</span>
<span class="muControl">reply-unless</span> next-node, new-node
<span class="Comment"># next-node.prev = new-node</span>
y<span class="Special"> <- </span>get-address *next-node, <span class="Constant">prev:offset</span>
*y<span class="Special"> <- </span>copy new-node
<span class="muControl">reply</span> new-node <span class="Comment"># just signalling something changed; don't rely on the result</span>
]
<span class="muScenario">scenario</span> inserting-into-duplex-list [
run [
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>copy <span class="Constant">0</span> <span class="Comment"># 1 points to head of list</span>
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">3</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">4</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">5</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">1</span>:address:duplex-list <span class="Comment"># 2 points inside list</span>
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>insert-duplex <span class="Constant">6</span>, <span class="Constant">2</span>:address:duplex-list
<span class="Comment"># check structure like before</span>
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>copy <span class="Constant">1</span>:address:duplex-list
<span class="Constant">3</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">4</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">5</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">6</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>prev-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">7</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>prev-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">8</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>prev-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">9</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">10</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">1</span>:address:duplex-list, <span class="Constant">2</span>:address:duplex-list
]
memory-should-contain [
<span class="Constant">3</span><span class="Special"> <- </span><span class="Constant">5</span> <span class="Comment"># scanning next</span>
<span class="Constant">4</span><span class="Special"> <- </span><span class="Constant">4</span>
<span class="Constant">5</span><span class="Special"> <- </span><span class="Constant">6</span> <span class="Comment"># inserted element</span>
<span class="Constant">6</span><span class="Special"> <- </span><span class="Constant">3</span>
<span class="Constant">7</span><span class="Special"> <- </span><span class="Constant">6</span> <span class="Comment"># then prev</span>
<span class="Constant">8</span><span class="Special"> <- </span><span class="Constant">4</span>
<span class="Constant">9</span><span class="Special"> <- </span><span class="Constant">5</span>
<span class="Constant">10</span><span class="Special"> <- </span><span class="Constant">1</span> <span class="Comment"># list back at start</span>
]
]
<span class="muScenario">scenario</span> inserting-at-end-of-duplex-list [
run [
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>copy <span class="Constant">0</span> <span class="Comment"># 1 points to head of list</span>
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">3</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">4</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">5</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">1</span>:address:duplex-list <span class="Comment"># 2 points inside list</span>
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list <span class="Comment"># now at end of list</span>
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>insert-duplex <span class="Constant">6</span>, <span class="Constant">2</span>:address:duplex-list
<span class="Comment"># check structure like before</span>
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>copy <span class="Constant">1</span>:address:duplex-list
<span class="Constant">3</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">4</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">5</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">6</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>prev-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">7</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>prev-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">8</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>prev-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">9</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">10</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">1</span>:address:duplex-list, <span class="Constant">2</span>:address:duplex-list
]
memory-should-contain [
<span class="Constant">3</span><span class="Special"> <- </span><span class="Constant">5</span> <span class="Comment"># scanning next</span>
<span class="Constant">4</span><span class="Special"> <- </span><span class="Constant">4</span>
<span class="Constant">5</span><span class="Special"> <- </span><span class="Constant">3</span>
<span class="Constant">6</span><span class="Special"> <- </span><span class="Constant">6</span> <span class="Comment"># inserted element</span>
<span class="Constant">7</span><span class="Special"> <- </span><span class="Constant">3</span> <span class="Comment"># then prev</span>
<span class="Constant">8</span><span class="Special"> <- </span><span class="Constant">4</span>
<span class="Constant">9</span><span class="Special"> <- </span><span class="Constant">5</span>
<span class="Constant">10</span><span class="Special"> <- </span><span class="Constant">1</span> <span class="Comment"># list back at start</span>
]
]
<span class="muScenario">scenario</span> inserting-after-start-of-duplex-list [
run [
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>copy <span class="Constant">0</span> <span class="Comment"># 1 points to head of list</span>
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">3</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">4</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">5</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>insert-duplex <span class="Constant">6</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Comment"># check structure like before</span>
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>copy <span class="Constant">1</span>:address:duplex-list
<span class="Constant">3</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">4</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">5</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">6</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>prev-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">7</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>prev-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">8</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>prev-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">9</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">10</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">1</span>:address:duplex-list, <span class="Constant">2</span>:address:duplex-list
]
memory-should-contain [
<span class="Constant">3</span><span class="Special"> <- </span><span class="Constant">5</span> <span class="Comment"># scanning next</span>
<span class="Constant">4</span><span class="Special"> <- </span><span class="Constant">6</span> <span class="Comment"># inserted element</span>
<span class="Constant">5</span><span class="Special"> <- </span><span class="Constant">4</span>
<span class="Constant">6</span><span class="Special"> <- </span><span class="Constant">3</span>
<span class="Constant">7</span><span class="Special"> <- </span><span class="Constant">4</span> <span class="Comment"># then prev</span>
<span class="Constant">8</span><span class="Special"> <- </span><span class="Constant">6</span>
<span class="Constant">9</span><span class="Special"> <- </span><span class="Constant">5</span>
<span class="Constant">10</span><span class="Special"> <- </span><span class="Constant">1</span> <span class="Comment"># list back at start</span>
]
]
<span class="Comment"># l:address:duplex-list <- remove-duplex in:address:duplex-list</span>
<span class="Comment"># Removes 'in' from its surrounding list. Returns some valid pointer into the</span>
<span class="Comment"># rest of the list.</span>
<span class="Comment">#</span>
<span class="Comment"># Returns null if and only if list is empty. Beware: in that case any pointers</span>
<span class="Comment"># to the head are now invalid.</span>
<span class="muRecipe">recipe</span> remove-duplex [
<span class="Constant">local-scope</span>
in:address:duplex-list<span class="Special"> <- </span><span class="Constant">next-ingredient</span>
<span class="Comment"># if 'in' is null, return</span>
<span class="muControl">reply-unless</span> in, in
next-node:address:duplex-list<span class="Special"> <- </span>get *in, <span class="Constant">next:offset</span>
prev-node:address:duplex-list<span class="Special"> <- </span>get *in, <span class="Constant">prev:offset</span>
<span class="Comment"># null in's pointers</span>
x:address:address:duplex-list<span class="Special"> <- </span>get-address *in, <span class="Constant">next:offset</span>
*x<span class="Special"> <- </span>copy <span class="Constant">0</span>
x<span class="Special"> <- </span>get-address *in, <span class="Constant">prev:offset</span>
*x<span class="Special"> <- </span>copy <span class="Constant">0</span>
<span class="Delimiter">{</span>
<span class="Comment"># if next-node is not null</span>
<span class="muControl">break-unless</span> next-node
<span class="Comment"># next-node.prev = prev-node</span>
x<span class="Special"> <- </span>get-address *next-node, <span class="Constant">prev:offset</span>
*x<span class="Special"> <- </span>copy prev-node
<span class="Delimiter">}</span>
<span class="Delimiter">{</span>
<span class="Comment"># if prev-node is not null</span>
<span class="muControl">break-unless</span> prev-node
<span class="Comment"># prev-node.next = next-node</span>
x<span class="Special"> <- </span>get-address *prev-node, <span class="Constant">next:offset</span>
*x<span class="Special"> <- </span>copy next-node
<span class="muControl">reply</span> prev-node
<span class="Delimiter">}</span>
<span class="muControl">reply</span> next-node
]
<span class="muScenario">scenario</span> removing-from-duplex-list [
run [
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>copy <span class="Constant">0</span> <span class="Comment"># 1 points to head of list</span>
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">3</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">4</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">5</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">1</span>:address:duplex-list <span class="Comment"># 2 points at second element</span>
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>remove-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">3</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">2</span>:address:duplex-list, <span class="Constant">0</span>
<span class="Comment"># check structure like before</span>
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>copy <span class="Constant">1</span>:address:duplex-list
<span class="Constant">4</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">5</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">6</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>prev-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">7</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">8</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">1</span>:address:duplex-list, <span class="Constant">2</span>:address:duplex-list
]
memory-should-contain [
<span class="Constant">3</span><span class="Special"> <- </span><span class="Constant">0</span> <span class="Comment"># remove returned non-null</span>
<span class="Constant">4</span><span class="Special"> <- </span><span class="Constant">5</span> <span class="Comment"># scanning next, skipping deleted element</span>
<span class="Constant">5</span><span class="Special"> <- </span><span class="Constant">3</span>
<span class="Constant">6</span><span class="Special"> <- </span><span class="Constant">0</span> <span class="Comment"># no more elements</span>
<span class="Constant">7</span><span class="Special"> <- </span><span class="Constant">5</span> <span class="Comment"># prev of final element</span>
<span class="Constant">8</span><span class="Special"> <- </span><span class="Constant">1</span> <span class="Comment"># list back at start</span>
]
]
<span class="muScenario">scenario</span> removing-from-start-of-duplex-list [
run [
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>copy <span class="Constant">0</span> <span class="Comment"># 1 points to head of list</span>
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">3</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">4</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">5</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Comment"># removing from head? return value matters.</span>
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>remove-duplex <span class="Constant">1</span>:address:duplex-list
<span class="Comment"># check structure like before</span>
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>copy <span class="Constant">1</span>:address:duplex-list
<span class="Constant">3</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">4</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">5</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>prev-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">6</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">7</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">1</span>:address:duplex-list, <span class="Constant">2</span>:address:duplex-list
]
memory-should-contain [
<span class="Constant">3</span><span class="Special"> <- </span><span class="Constant">4</span> <span class="Comment"># scanning next, skipping deleted element</span>
<span class="Constant">4</span><span class="Special"> <- </span><span class="Constant">3</span>
<span class="Constant">5</span><span class="Special"> <- </span><span class="Constant">0</span> <span class="Comment"># no more elements</span>
<span class="Constant">6</span><span class="Special"> <- </span><span class="Constant">4</span> <span class="Comment"># prev of final element</span>
<span class="Constant">7</span><span class="Special"> <- </span><span class="Constant">1</span> <span class="Comment"># list back at start</span>
]
]
<span class="muScenario">scenario</span> removing-from-end-of-duplex-list [
run [
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>copy <span class="Constant">0</span> <span class="Comment"># 1 points to head of list</span>
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">3</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">4</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">5</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Comment"># delete last element</span>
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">1</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>remove-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">3</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">2</span>:address:duplex-list, <span class="Constant">0</span>
<span class="Comment"># check structure like before</span>
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>copy <span class="Constant">1</span>:address:duplex-list
<span class="Constant">4</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">5</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">6</span>:address:duplex-list<span class="Special"> <- </span>next-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>prev-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">7</span>:number<span class="Special"> <- </span>first-duplex <span class="Constant">2</span>:address:duplex-list
<span class="Constant">8</span>:boolean<span class="Special"> <- </span>equal <span class="Constant">1</span>:address:duplex-list, <span class="Constant">2</span>:address:duplex-list
]
memory-should-contain [
<span class="Constant">3</span><span class="Special"> <- </span><span class="Constant">0</span> <span class="Comment"># remove returned non-null</span>
<span class="Constant">4</span><span class="Special"> <- </span><span class="Constant">5</span> <span class="Comment"># scanning next, skipping deleted element</span>
<span class="Constant">5</span><span class="Special"> <- </span><span class="Constant">4</span>
<span class="Constant">6</span><span class="Special"> <- </span><span class="Constant">0</span> <span class="Comment"># no more elements</span>
<span class="Constant">7</span><span class="Special"> <- </span><span class="Constant">5</span> <span class="Comment"># prev of final element</span>
<span class="Constant">8</span><span class="Special"> <- </span><span class="Constant">1</span> <span class="Comment"># list back at start</span>
]
]
<span class="muScenario">scenario</span> removing-from-singleton-list [
run [
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>copy <span class="Constant">0</span> <span class="Comment"># 1 points to singleton list</span>
<span class="Constant">1</span>:address:duplex-list<span class="Special"> <- </span>push-duplex <span class="Constant">3</span>, <span class="Constant">1</span>:address:duplex-list
<span class="Constant">2</span>:address:duplex-list<span class="Special"> <- </span>remove-duplex <span class="Constant">1</span>:address:duplex-list
<span class="Constant">3</span>:address:duplex-list<span class="Special"> <- </span>get *<span class="Constant">1</span>:address:duplex-list, <span class="Constant">next:offset</span>
<span class="Constant">4</span>:address:duplex-list<span class="Special"> <- </span>get *<span class="Constant">1</span>:address:duplex-list, <span class="Constant">prev:offset</span>
]
memory-should-contain [
<span class="Constant">2</span><span class="Special"> <- </span><span class="Constant">0</span> <span class="Comment"># remove returned null</span>
<span class="Constant">3</span><span class="Special"> <- </span><span class="Constant">0</span> <span class="Comment"># removed node is also detached</span>
<span class="Constant">4</span><span class="Special"> <- </span><span class="Constant">0</span>
]
]
</pre>
</body>
</html>
<!-- vim: set foldmethod=manual : -->