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22 <div class="head1">The Formal System λδ (\lambda\delta)</div>
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34 <a href="http://lambdadelta.info/index.html">foreword</a>
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37 <a href="http://lambdadelta.info/news.html">news</a>
39 <td class="snns component orange">
40 <a href="http://lambdadelta.info/documentation.html">documentation</a>
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43 <a href="http://lambdadelta.info/implementation.html">implementation</a>
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59 <td class="snns magenta">
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65 <td class="snns green">
66 <a href="http://lambdadelta.info/version_2.html">Version 2</a>
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69 <a href="http://lambdadelta.info/ground_2.html">Background</a>
71 <td class="snnn green">
72 <a href="http://lambdadelta.info/basic_2.html">Core</a>
74 <td class="ssnn green">
75 <a href="http://lambdadelta.info/apps_2.html">Applications</a>
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89 <a href="http://lambdadelta.info/version_1.html">Version 1</a>
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94 <td class="snsn green">
97 <td class="sssn green">
105 <div xmlns:ld="http://lambdadelta.info/" class="head2dx" id="milestones">Milestones <img class="icon37" alt="[spacer]" title="lambdadelta butterfly" src="http://lambdadelta.info/images/b5.png" />
107 <div xmlns:ld="http://lambdadelta.info/" class="text">
110 <span class="date">June 2014.</span>
111 <a href="http://lambdadelta.info/documentation.html#ldt8">First communication on λδ version 2.</a>
116 <span class="date">December 2012.</span>
117 The character "_" is removed from the denomination "lambda_delta":
120 The denomination "\lambda\delta" is used in λδ-related texts.
123 The denomination "lambdadelta" is used in λδ-related identifiers.
126 Permanent λδ URL acquired:
127 <a href="http://lambdadelta.info/">http://lambdadelta.info/</a>
128 (pointing at this site).
135 <span class="date">September 2011.</span>
136 The denomination "lambda-delta" changes to "lambda_delta":
139 The character "-" is reserved in λδ textual syntax
140 (recognized by "Helena 0.8.1").
143 Eventually, the occurrences of the character "-"
144 will be replaced by "_" in all λδ-related identifiers.
147 In particular, this refactoring involves file names and path names.
154 <span class="date">April 2011.</span>
155 The specification of <a href="http://lambdadelta.info/version_2.html">λδ version 2</a>
156 and related topics is restarted in
157 <a href="http://matita.cs.unibo.it/">Matita 0.5</a>.
162 <span class="date">December 2010.</span>
163 Transient λδ URL acquired: http://lambda-delta.info/ (expires on December 2012).
168 <span class="date">November 2010.</span>
169 "Helena 0.8.1" is released.
174 <span class="date">September 2009.</span>
175 "Helena 0.8.0" is released and the
176 <a href="http://lambdadelta.info/implementation.html#lddl">λδ Digital Library</a>
182 <span class="date">June 2009.</span>
183 "Helena", a <a href="http://lambdadelta.info/implementation.html#helena">validator for λδ version 2</a>,
184 is available as a part of the <a href="http://helm.cs.unibo.it/">HELM</a> software.
189 <span class="date">September 2008.</span>
195 <span class="date">July 2008.</span>
196 <a href="http://lambdadelta.info/documentation.html#ldp5">First journal paper on λδ</a>
197 accepted for publication.
202 <span class="date">July 2008.</span>
203 First <a href="http://helm.cs.unibo.it/procedural/">procedural reconstruction</a>
204 for <a href="http://matita.cs.unibo.it/">Matita 0.5</a>
205 of the λδ version 1 for Coq 7.3.1.
210 <span class="date">June 2008.</span>
211 The <a href="http://lambdadelta.info/version_1.html#static">
212 HTML pages of the specification of λδ version 1 for Matita 0.5</a>
218 <span class="date">May 2008.</span>
219 The specification of λδ version 1 is dismissed.
224 <span class="date">March 2008.</span>
225 The specification of λδ version 2 is started with Coq 7.3.1 (false start).
230 <span class="date">September 2007.</span>
231 The <a href="http://lambdadelta.info/version_1.html#dynamic">
232 specification of λδ version 1 for Matita 0.4</a>
238 <span class="date">November 2006.</span>
239 <a href="http://lambdadelta.info/documentation.html#ldp3">λδ version 1</a>
245 <span class="date">December 2005.</span>
246 <a href="http://lambdadelta.info/documentation.html#ldt1">First communication on λδ</a>.
251 <span class="date">May 2004.</span>
252 The specification of <a href="http://lambdadelta.info/version_1.html">λδ version 1</a>
253 is started with Coq 7.3.1.
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260 <div xmlns:ld="http://lambdadelta.info/" class="text">
263 <span class="date">June 2014.</span>
264 The <a href="http://www.google.com/">Google</a>
265 search for "formal system lambda delta" gives
266 5 resources about λδ in the first 6 results.
271 <span class="date">June 2014.</span>
272 The <a href="http://www.yahoo.com/">Yahoo</a>
273 search for "formal system lambda delta" gives
274 4 resources about λδ in the first 5 results.
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305 <div xmlns:ld="http://lambdadelta.info/" class="spacer">Last update: Sun, 13 Jul 2014 23:25:31 +0200</div>