-<head>
- <meta content="text/html; charset=UTF-8" http-equiv="content-type">
- <title>lambda_delta home page</title>
- <meta content="Ferruccio Guidi" name="author">
- <meta content="The formal system lambda_delta" name="description">
- <link rel="shortcut icon" href="download/crux_16.ico">
-</head>
-<body>
-<div style="text-align: center;">
-<br>
-<a href="http://lambda-delta.info"><img alt="[Crux Logo]"
- title="The Crux" src="download/crux_32.png"
- style="border: 0px solid ; width: 32px; height: 32px;"></a>
-<h1>The Formal System λδ (lambda_delta)<br>
-</h1>
-<h2>Towards the unification of terms, types, environments and contexts</h2>
-<img style="width: 95%; height: 4px;" alt="[Separator]"
- title="Separator" src="download/rainbow.png"><br>
-<table
- style="text-align: left; width: 95%; margin-left: auto; margin-right: auto;"
- border="0" cellpadding="2" cellspacing="20">
- <tbody>
- <tr>
- <td style="vertical-align: top;">
- <ul>
- <li><a href="index.html">Foreword</a></li>
- </ul>
- <ul>
- <li><a href="news.html">News</a></li>
- </ul>
- <ul>
- <li><a href="documentation.html">Papers</a></li>
- </ul>
- <ul>
- <li>Resources<br>
- </li>
- </ul>
- </td>
- <td style="vertical-align: top; text-align: left;">
- <h3 style="text-align: right;">Computer-checked formal
-specifications <img style="width: 37px; height: 37px;"
- alt="[Butterfly]" title="Butterfly" src="download/b9.png"></h3>
- <span style="font-weight: bold;">Resource
-1</span> below provides for the statically generated <span
- style="font-weight: bold;">natural language representation</span> of
-λδ meta-theory (faster rendering w.r.t. resource 2 below).<br>
- <span style="font-weight: bold;">Resource 2</span> below provides
-for the dynamically generated <span style="font-weight: bold;">natural
-language representation</span> of
-λδ meta-theory (powered by the <a href="http://helm.cs.unibo.it/">HELM</a>
-rendering engine).<br>
-Remarkably, λδ was born and developed in the digital format of <span
- style="font-weight: bold;">resource 3</span> below, which is not the
-formal counterpart of some informal material previously written on
-paper (as it happens for most currently digitalized Mathematics).<br>
- <ol>
- <li><a name="static"></a>F. Guidi: <a
- style="font-style: italic;" href="static/matita/lambda_delta/">lambda_delta</a>
-(revised <span style="font-weight: bold;">2011-09</span>). Formal
-specification with the proof assistant <a
- href="http://matita.cs.unibo.it/">Matita</a> 0.5 (HTML pages generated
-by the <a href="http://helm.cs.unibo.it/">HELM</a>
-rendering engine)<br>
-Here are the most relevant theorems proved in the formal specification:
- <ul>
- <li><a
- href="static/matita/lambda_delta/Basic_1/pr3/pr3/pr3_confluence.con.html">Confluence
-of
-reduction</a> (Church-Rosser property).</li>
- <li><a
- href="static/matita/lambda_delta/Basic_1/ty3/props/ty3_correct.con.html">Correctness
-of
-types</a>.</li>
- <li><a
- href="static/matita/lambda_delta/Basic_1/ty3/props/ty3_unique.con.html">Uniqueness
-of
-types
-up
-to
-conversion</a>.<br>
- </li>
- <li><a
- href="static/matita/lambda_delta/Basic_1/ty3/pr3/ty3_sred_pr3.con.html">Subject
-reduction
-of
-the
-type
-assignment</a>.</li>
- <li><a
- href="static/matita/lambda_delta/Basic_1/ty3/arity_props/ty3_sn3.con.html">Strong
-normalization
-of
-the
-typed
-terms</a>.</li>
- <li><a
- href="static/matita/lambda_delta/Basic_1/ty3/dec/ty3_inference.con.html">Decidability
-of
-the
-type
-inference
-problem</a>.<br>
+ <head>
+ <meta content="text/html; charset=UTF-8" http-equiv="content-type">
+ <title>lambda_delta home page</title>
+ <meta content="Ferruccio Guidi" name="author">
+ <meta content="The formal system lambda_delta" name="description">
+ <link rel="shortcut icon" href="download/crux_16.ico">
+ </head>
+ <body>
+ <div style="text-align: center;">
+ <br>
+ <a href="http://lambda-delta.info"><img alt="[Crux Logo]"
+ title="The Crux" src="download/crux_32.png" style="border: 0px
+ solid ; width: 32px; height: 32px;"></a>
+ <h1>The Formal System λδ (lambda_delta)<br>
+ </h1>
+ <h2>Towards the unification of terms, types, environments and
+ contexts</h2>
+ <img style="width: 95%; height: 4px;" alt="[Separator]"
+ title="Separator" src="download/rainbow.png"><br>
+ <table style="text-align: left; width: 95%; margin-left: auto;
+ margin-right: auto;" border="0" cellpadding="2" cellspacing="20">
+ <tbody>
+ <tr>
+ <td style="vertical-align: top;">
+ <ul>
+ <li><a href="index.html">Foreword</a></li>
+ </ul>
+ <ul>
+ <li><a href="news.html">News</a></li>
+ </ul>
+ <ul>
+ <li><a href="documentation.html">Papers</a></li>
+ </ul>
+ <ul>
+ <li>Resources<br>
+ </li>
+ </ul>
+ </td>
+ <td style="vertical-align: top; text-align: left;">
+ <h3 style="text-align: right;">Computer-checked formal
+ specifications <img style="width: 37px; height: 37px;"
+ alt="[Butterfly]" title="Butterfly"
+ src="download/b9.png"></h3>
+ <span style="font-weight: bold;">Resource
+ 1</span> below provides for the statically generated <span
+ style="font-weight: bold;">natural language
+ representation</span> of
+ λδ meta-theory (faster rendering w.r.t. resource 2 below).<br>
+ <span style="font-weight: bold;">Resource 2</span> below
+ provides
+ for the dynamically generated <span style="font-weight:
+ bold;">natural
+ language representation</span> of
+ λδ meta-theory (powered by the <a
+ href="http://helm.cs.unibo.it/">HELM</a>
+ rendering engine).<br>
+ Remarkably, λδ was born and developed in the digital
+ format of <span style="font-weight: bold;">resource 3</span>
+ below, which is not the
+ formal counterpart of some informal material previously
+ written on
+ paper (as it happens for most currently digitalized
+ Mathematics).<br>
+ <ol>
+ <li><a name="static"></a>F. Guidi: <a
+ style="font-style: italic;"
+ href="static/matita/lambda_delta/">lambda_delta</a>
+ (revised <span style="font-weight: bold;">2011-09</span>).
+ Formal
+ specification for <a
+ href="http://matita.cs.unibo.it/">Matita</a> 0.5
+ (HTML pages generated
+ by the <a href="http://helm.cs.unibo.it/">HELM</a>
+ rendering engine)<br>
+ Here are the most relevant theorems proved in the
+ formal specification:
+ <ul>
+ <li><a
+href="static/matita/lambda_delta/Basic_1/pr3/pr3/pr3_confluence.con.html">Confluence
+ of
+ reduction</a> (Church-Rosser property).</li>
+ <li><a
+ href="static/matita/lambda_delta/Basic_1/ty3/props/ty3_correct.con.html">Correctness
+ of
+ types</a>.</li>
+ <li><a
+ href="static/matita/lambda_delta/Basic_1/ty3/props/ty3_unique.con.html">Uniqueness
+ of
+ types
+ up
+ to
+ conversion</a>.<br>
+ </li>
+ <li><a
+ href="static/matita/lambda_delta/Basic_1/ty3/pr3/ty3_sred_pr3.con.html">Subject
+ reduction
+ of
+ the
+ type
+ assignment</a>.</li>
+ <li><a
+href="static/matita/lambda_delta/Basic_1/ty3/arity_props/ty3_sn3.con.html">Strong
+ normalization
+ of
+ the
+ typed
+ terms</a>.</li>
+ <li><a
+ href="static/matita/lambda_delta/Basic_1/ty3/dec/ty3_inference.con.html">Decidability
+ of
+ the
+ type
+ inference
+ problem</a>.<br>
+ <br>
+ </li>
+ </ul>
+ </li>
+ <li><a name="dynamic"></a>F. Guidi: <a
+ style="font-style: italic;"
+href="http://mowgli.cs.unibo.it:58080/apply?keys=RT&xmluri=http://helm.cs.unibo.it/helm//html/folder/index.html&prop.media-type=text/html&param.thmedia-type=text/html&param.thkeys=T1%2CT2%2CL%2CE&param.embedkeys=d_c%2CTC1%2CHC2%2CL&param.thencoding=UTF-8&prop.encoding=UTF-8&prop.doctype-public=-//W3C//DTD%20XHTML%201.0%20Transitional//EN&param.doctype-public=-//W3C//DTD%20XHTML%201.0%20Transitional//EN&param.encoding=UTF-8&param.media-type=text/html&param.keys=d_c%2CC1%2CHC2%2CL&profile=default&param.profile=default&param.CICURI=theory:/matita/lambda_delta/">lambda_delta</a>
+ (revised <span style="font-weight: bold;">2011-09</span>).
+ Formal
+ specification for <a
+ href="http://matita.cs.unibo.it/">Matita</a> 0.5 (<a
+ href="http://helm.cs.unibo.it/">HELM</a> directory).<br>
+ <br>
+ </li>
+ <li><a name="ldp1"></a>F. Guidi: <a
+ href="download/lambda_delta_1.tar.gz"><span
+ style="font-style: italic;">lambda_delta_1</span></a>
+ (revised <span style="font-weight: bold;">2011-09</span>).
+Formal
+ specification for <span style="font-weight: bold;">Coq
+ 7.3.1</span>
+ (source
+ proof scripts). <a href="#bibtex">BibTeX entry</a>.<br>
+ </li>
+ </ol>
+ <h3 style="text-align: right;">Tools <img style="width:
+ 37px; height: 37px;" alt="[Butterfly]"
+ title="Butterfly" src="download/b5.png"></h3>
+ <a name="lddl"></a><img style="width: 32px; height: 32px;"
+ alt="[Crux Logo]" title="The Crux"
+ src="download/crux_32.png"><span style="font-weight:
+ bold;"> </span>The <span style="font-weight: bold;"><span
+ style="text-decoration: underline;">λδ
+ Digital
+ Library
+ (LDDL)</span></span> is part of <a
+ href="http://helm.cs.unibo.it/">HELM</a>
+ and contains a set of
+ resources expressed in λδ.<br>
+ <ul>
+ <li><span style="font-weight: bold;">Contents:</span>
+ Landau's "<span style="font-style: italic;">Grundlagen
+ der Analysis</span>" (from
+ Jutting's specification in <a
+ href="http://www.win.tue.nl/automath/">Automath</a>).<br>
+ <span style="font-weight: bold;"></span></li>
+ </ul>
+ <ul>
+ <li><span style="font-weight: bold;">Access:</span> <a
+ href="static/lddl/">static pages</a> (updated <span
+ style="font-weight: bold;">2011-09</span>), <a
+ href="download/lddl.tar.bz2">data set</a> (updated <span
+ style="font-weight: bold;">2011-09</span>), <a
+ href="http://lambda-delta.info/xml">HELM server URL</a>
+ (updated <span style="font-weight: bold;">2011-09</span>).</li>
+ </ul>
+ <ul>
+ <li><span style="font-weight: bold;">Examples:</span> <a
+href="static/lddl/brg_si/grundlagen/l/e/st/eq/landau/n/rt/rp/r/c/8283/t234.ld.html">Grundlagen's
+ definition
+ "t234"</a> (in "basic_rg" λδ), <a
+href="static/lddl/crg_si/grundlagen/l/e/st/eq/landau/n/rt/rp/r/c/8283/t234.ld.html">Grundlagen's
+ definition
+ "t234"</a> (in "complete_rg" λδ).<br>
+ </li>
+ </ul>