helm/www/lambdadelta/news.html

   1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
   2 <html>
   3 <head>
   4   <meta content="text/html; charset=UTF-8" http-equiv="content-type">
   5   <title>lambdadelta home page</title>
   6   <meta content="Ferruccio Guidi" name="author">
   7   <meta content="The formal system lambdadelta" name="description">
   8   <link rel="shortcut icon" href="download/crux_16.ico">
   9 </head>
  10 <body>
  11 <div style="text-align: center;"> <br>
  12 <a href="http://lambdadelta.info"><img alt="[Crux Logo]"
  13  title="The Crux" src="download/crux_32.png"
  14  style="border: 0px solid ; width: 32px; height: 32px;"></a>
  15 <h1>The Formal System λδ (lambdadelta)<br>
  16 </h1>
  17 <h2>Towards the unification of terms, types, environments and contexts</h2>
  18 <img style="width: 95%; height: 4px;" alt="[Separator]"
  19  title="Separator" src="download/rainbow.png"><br>
  20 <table
  21  style="text-align: left; width: 95%; margin-left: auto; margin-right: auto;"
  22  border="0" cellpadding="2" cellspacing="20">
  23   <tbody>
  24     <tr>
  25       <td style="vertical-align: top;">
  26       <ul>
  27         <li><a href="index.html">Foreword</a></li>
  28       </ul>
  29       <ul>
  30         <li>News</li>
  31       </ul>
  32       <ul>
  33         <li><a href="documentation.html">Papers</a></li>
  34       </ul>
  35       <ul>
  36         <li><a href="implementation.html">Resources</a><br>
  37         </li>
  38       </ul>
  39       </td>
  40       <td style="vertical-align: top; text-align: left;">
  41       <h3 style="text-align: right;">News <img
  42  style="width: 37px; height: 37px;" alt="[Butterfly]" title="Butterfly"
  43  src="download/b5.png"></h3>
  44       <ul>
  45         <li><span style="font-weight: bold;">September 2011.</span> The
  46 denomination "lambdadelta" changes to "lambdadelta".
  47           <ul>
  48             <li>The character "-" is reserved in λδ textual syntax
  49 (recognized by <span style="font-style: italic;">Helena 0.8.1</span>).
  50             </li>
  51             <li>Eventually, the occurrences of the character "-" will
  52 be replaced by "_" in all λδ-related identifiers.</li>
  53             <li>In particular, this refactoring involves file names and
  54 path names.</li>
  55             <li>The permanent λδ URL is sheduled to become <span
  56  style="font-style: italic;">http://lambdadelta.info</span> on
  57 December 2012.<br>
  58             </li>
  59           </ul>
  60         </li>
  61       </ul>
  62       <ul>
  63         <li><span style="font-weight: bold;">April 2011.</span> The
  64 specification of λδ version 2 and related topics is restarted in <a
  65  href="http://matita.cs.unibo.it/">Matita 0.5</a>.
  66           <ul>
  67             <li><a href="apps_2.html">Here</a> is a page about the
  68 topics related to the specification (Applications).</li>
  69             <li><a href="basic_2.html">Here</a> is a page about the
  70 specification (Core). </li>
  71           </ul>
  72         </li>
  73       </ul>
  74       <ul>
  75         <li><span style="font-weight: bold;">December 2010.</span>
  76 Permanent λδ URL acquired: <a href="http://lambdadelta.info">http://lambdadelta.info</a>
  77 (pointing at this site). <br>
  78           <span style="font-weight: bold;"></span></li>
  79       </ul>
  80       <ul>
  81         <li><span style="font-weight: bold;">November 2010.</span> <span
  82  style="font-style: italic;">Helena 0.8.1</span> is released. <br>
  83         </li>
  84       </ul>
  85       <ul>
  86         <li><span style="font-weight: bold;">September 2009.</span> <span
  87  style="font-style: italic;">Helena 0.8.0</span> is released and the <a
  88  href="implementation.html#lddl">λδ Digital Library</a> is started.<br>
  89           <span style="font-weight: bold;"></span></li>
  90       </ul>
  91       <ul>
  92         <li><span style="font-weight: bold;">June 2009.</span> <span
  93  style="font-style: italic;">Helena</span>, a <a
  94  href="implementation.html#helena">validator for λδ version 2</a>, is
  95 available as a part of the <a href="http://helm.cs.unibo.it/">HELM</a>
  96 software. <br>
  97         </li>
  98       </ul>
  99       <span style="font-weight: bold;"></span>
 100       <ul>
 101         <li><span style="font-weight: bold;">September 2008.</span>
 102 This site is online.<br>
 103         </li>
 104       </ul>
 105       <span style="font-weight: bold;"></span>
 106       <ul>
 107         <li><span style="font-weight: bold;">July 2008.</span> <a
 108  href="documentation.html#ldp5">First journal paper on λδ</a> accepted
 109 for publication.</li>
 110       </ul>
 111       <ul>
 112         <li><span style="font-weight: bold;">July 2008.</span> First <a
 113  href="http://helm.cs.unibo.it/procedural/">procedural reconstruction</a>
 114 for <a href="http://matita.cs.unibo.it/">Matita 0.5</a> of the <a
 115  href="implementation.html#ldp1">λδ proof scripts for Coq 7.3.1</a>.<br>
 116         </li>
 117       </ul>
 118       <ul>
 119         <li><span style="font-weight: bold;">June 2008.</span> The <a
 120  href="implementation.html#static">HTML pages of the specification of
 121 λδ version 1 for Matita 0.5</a> are online.<br>
 122           <span style="font-weight: bold;"></span></li>
 123       </ul>
 124       <ul>
 125         <li><span style="font-weight: bold;">May 2008.</span> The
 126 specification of λδ version 1 is closed.<br>
 127           <span style="font-weight: bold;"></span></li>
 128       </ul>
 129       <ul>
 130         <li><span style="font-weight: bold;">March 2008.</span> The
 131 specification of λδ version 2 is started with Coq 7.3.1 (false start). </li>
 132       </ul>
 133 <!--          <ul>
 134             <li>native type assignment with new rules for application: <span
 135  style="font-style: italic;">nty</span> (it replaces <span
 136  style="font-style: italic;">ty3</span>);<br>
 137             </li>
 138             <li>parallel conversion on focalized terms: <span
 139  style="font-style: italic;">fpcs</span> (it replaces <span
 140  style="font-style: italic;"></span><span style="font-style: italic;">pc3</span>);
 141               <br>
 142             </li>
 143             <li>new weak parallel reduction on environments: <span
 144  style="font-style: italic;">wcpr</span> <span
 145  style="font-style: italic;"></span>(it is based on <span
 146  style="font-style: italic;">fpr</span> and replaces <span
 147  style="font-style: italic;">wcpr0</span>);&nbsp; <br>
 148             </li>
 149             <li>parallel reduction on focalized terms: <span
 150  style="font-style: italic;">fpr</span> and <span
 151  style="font-style: italic;">fprs</span> (they replace <span
 152  style="font-style: italic;"></span><span style="font-style: italic;"></span><span
 153  style="font-style: italic;">pr2</span>, <span
 154  style="font-style: italic;">pr3</span>); <br>
 155             </li>
 156           </ul>
 157           <ul>
 158             <li>new thinning relation: <span
 159  style="font-style: italic;">drop</span>
 160 (it replaces the old <span style="font-style: italic;">drop</span>, <span
 161  style="font-style: italic;">clear</span>, <span
 162  style="font-style: italic;">getl</span>, <span
 163  style="font-style: italic;">cimp</span>, <span
 164  style="font-style: italic;">drop1</span>);</li>
 165             <li>new shift function: <span style="font-style: italic;">shift</span>:
 166 (it
 167 replaces
 168
 169               <span style="font-style: italic;">app1</span>);</li>
 170             <li>new length function for environments: <span
 171  style="font-style: italic;">clen</span>;<br>
 172             </li>
 173             <li>new relocation function: <span
 174  style="font-style: italic;">lift</span> (it replaces old <span
 175  style="font-style: italic;">lift</span>, <span
 176  style="font-style: italic;">lift1</span>);<br>
 177             </li>
 178             <li>new term structure with polarity indicators and no
 179 distinction between binding and flat items;</li>
 180             <li>new general theory of relocation (comprises new
 181 relocation functions: <span style="font-style: italic;">s</span>, <span
 182  style="font-style: italic;">r</span>);</li>
 183             <li>we removed context-free reduction and conversion (<span
 184  style="font-style: italic;">pr0</span>, <span
 185  style="font-style: italic;">pr1</span>, <span
 186  style="font-style: italic;">pc1</span>);<br>
 187             </li>
 188             <li>we removed greedy substitution (<span
 189  style="font-style: italic;"></span><span style="font-style: italic;">csubst0</span>,
 190               <span style="font-style: italic;">csubst1</span>, <span
 191  style="font-style: italic;">fsubst0</span>, <span
 192  style="font-style: italic;">subst0</span>, <span
 193  style="font-style: italic;">subst1</span>);<br>
 194             </li>
 195             <li>we removed level indicators on environments (<span
 196  style="font-style: italic;">cbk</span>).</li>
 197           </ul>
 198 -->
 199       <ul>
 200         <li><span style="font-weight: bold;">September 2007.</span> The
 201           <a href="implementation.html#dynamic">specification of λδ
 202 version 1 for Matita 0.4</a> is online.</li>
 203       </ul>
 204       <ul>
 205         <li><span style="font-weight: bold;">November 2006.</span> <a
 206  href="documentation.html#ldp3">λδ version 1</a> is released.</li>
 207       </ul>
 208       <ul>
 209         <li><span style="font-weight: bold;">December 2005.</span> <a
 210  href="documentation.html#ldt1">First communication on λδ</a>.<br>
 211         </li>
 212       </ul>
 213       <ul>
 214         <li><span style="font-weight: bold;">May 2004.</span> The <a
 215  href="implementation.html#ldp1">specification of λδ version 1</a> is
 216 started with Coq 7.3.1.<br>
 217         </li>
 218       </ul>
 219       <h3 style="text-align: right;">Visibility <img
 220  style="width: 37px; height: 37px;" alt="[Butterfly]" title="Butterfly"
 221  src="download/b4.png"></h3>
 222       <ul>
 223         <li><span style="font-weight: bold;">February 2012.</span> The <a
 224  href="http://www.google.com/">Google</a> search for <span
 225  style="color: rgb(255, 0, 0);">formal system lambda delta</span> gives
 226 5 resources about λδ in the first 6 results.<br>
 227         </li>
 228       </ul>
 229       <ul>
 230         <li><span style="font-weight: bold;">February 2012.</span> The <a
 231  href="http://www.yahoo.com/">Yahoo</a> search <span
 232  style="color: rgb(255, 0, 0);">formal system lambda delta</span> gives
 233 this site as the first result.</li>
 234       </ul>
 235       </td>
 236     </tr>
 237   </tbody>
 238 </table>
 239 <br>
 240 <a href="http://validator.w3.org/check?uri=referer"><img
 241  alt="[Valid HTML 4.01 Transitional]"
 242  title="Valid HTML 4.01
 243           Transitional"
 244  src="http://www.w3.org/Icons/valid-html401"
 245  style="border: 0px solid ; width: 88px; height: 31px;"></a> <a
 246  href="http://www.anybrowser.org/campaign/"><img
 247  alt="[Use Any
 248           Browser Here]" title="Use Any Browser Here"
 249  src="download/globe_trans.png"
 250  style="border: 0px solid ; width: 147px; height: 42px;"></a> <img
 251  style="width: 88px; height: 31px;" alt="[PNG Used Here]"
 252  title="PNG Used Here" src="download/PNGnow2.png"><br>
 253 <br>
 254 Last update 2012-12-01 by <a href="http://www.cs.unibo.it/%7Efguidi/">Ferruccio
 255
 256 Guidi</a><br>
 257 </div>
 258 </body>
 259 </html>