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22 <div class="head1">The Formal System λδ (\lambda\delta)</div>
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33 <td class="snns capitalize italic sky">
34 <a href="http://lambdadelta.info/index.html">home</a>
36 <td class="snns capitalize italic magenta">
37 <a href="http://lambdadelta.info/news.html">news</a>
39 <td class="snns capitalize italic orange">
40 <a href="http://lambdadelta.info/documentation.html">documentation</a>
42 <td class="snns capitalize italic green">
43 <a href="http://lambdadelta.info/implementation.html">implementation</a>
45 <td class="ssnn capitalize italic green">(<a href="http://lambdadelta.info/implementation.html#specifications">specifications</a> - <a href="http://lambdadelta.info/implementation.html#lddl">library</a> - <a href="http://lambdadelta.info/implementation.html#helena">Helena</a>)</td>
49 <a href="http://lambdadelta.info/index.html#foreword">Foreword</a>
51 <td class="snns magenta">
52 <a href="http://lambdadelta.info/news.html#milestones">Milestones</a>
54 <td class="snns orange">
55 <a href="http://lambdadelta.info/documentation.html#v2">Version 2</a>
57 <td class="snns green">
58 <a href="http://lambdadelta.info/version_2.html">Version 2</a>
60 <td class="ssnn green">(<a href="http://lambdadelta.info/ground_2.html">Background</a> - <a href="http://lambdadelta.info/basic_2.html">Core</a> - <a href="http://lambdadelta.info/apps_2.html">Applications</a>)</td>
64 <a href="http://lambdadelta.info/index.html#notice">Notice</a>
66 <td class="snss magenta">
67 <a href="http://lambdadelta.info/news.html#visibility">Visibility</a>
69 <td class="snss orange">
70 <a href="http://lambdadelta.info/documentation.html#v1">Version 1</a>
72 <td class="snss green">
73 <a href="http://lambdadelta.info/version_1.html">Version 1</a>
75 <td class="sssn green">
83 <div xmlns:ld="http://lambdadelta.info/" class="head2dx" id="milestones">Milestones <img class="icon37" alt="[spacer]" title="lambdadelta butterfly" src="http://lambdadelta.info/images/b3.png" />
86 <ul xmlns:ld="http://lambdadelta.info/">
88 <span class="date">July 2014.</span>
89 A new version of this site is online.
93 <ul xmlns:ld="http://lambdadelta.info/">
95 <span class="date">June 2014.</span>
96 <a href="http://lambdadelta.info/documentation.html#ldP8">First communication on λδ version 2.</a>
100 <ul xmlns:ld="http://lambdadelta.info/">
102 <span class="date">December 2012.</span>
103 The character "_" is removed from the denomination "lambda_delta":
106 The denomination "\lambda\delta" is used in λδ-related texts.
109 The denomination "lambdadelta" is used in λδ-related identifiers.
112 Permanent λδ URL acquired:
113 <a href="http://lambdadelta.info/">http://lambdadelta.info/</a>
114 (pointing at this site).
120 <ul xmlns:ld="http://lambdadelta.info/">
122 <span class="date">September 2011.</span>
123 The denomination "lambda-delta" changes to "lambda_delta":
126 The character "-" is reserved in λδ textual syntax
127 (recognized by "Helena 0.8.1").
130 Eventually, the occurrences of the character "-"
131 will be replaced by "_" in all λδ-related identifiers.
134 In particular, this refactoring involves file names and path names.
140 <ul xmlns:ld="http://lambdadelta.info/">
142 <span class="date">April 2011.</span>
143 The specification of <a href="http://lambdadelta.info/version_2.html">λδ version 2</a>
144 and related topics is restarted in
145 <a href="http://matita.cs.unibo.it/">Matita 0.5</a>.
149 <ul xmlns:ld="http://lambdadelta.info/">
151 <span class="date">December 2010.</span>
152 Transient λδ URL acquired: http://lambda-delta.info/ (expires on December 2012).
156 <ul xmlns:ld="http://lambdadelta.info/">
158 <span class="date">November 2010.</span>
159 "Helena 0.8.1" is released.
163 <ul xmlns:ld="http://lambdadelta.info/">
165 <span class="date">September 2009.</span>
166 "Helena 0.8.0" is released and the
167 <a href="http://lambdadelta.info/implementation.html#lddl">λδ Digital Library</a>
172 <ul xmlns:ld="http://lambdadelta.info/">
174 <span class="date">June 2009.</span>
175 "Helena", a <a href="http://lambdadelta.info/implementation.html#helena">validator for λδ version 2</a>,
176 is available as a part of the <a href="http://helm.cs.unibo.it/">HELM</a> software.
180 <ul xmlns:ld="http://lambdadelta.info/">
182 <span class="date">September 2008.</span>
187 <ul xmlns:ld="http://lambdadelta.info/">
189 <span class="date">July 2008.</span>
190 <a href="http://lambdadelta.info/documentation.html#ldJ1">First journal paper on λδ</a>
191 accepted for publication.
195 <ul xmlns:ld="http://lambdadelta.info/">
197 <span class="date">July 2008.</span>
198 First <a href="http://helm.cs.unibo.it/procedural/">procedural reconstruction</a>
199 for <a href="http://matita.cs.unibo.it/">Matita 0.5</a>
200 of the λδ version 1 for Coq 7.3.1.
204 <ul xmlns:ld="http://lambdadelta.info/">
206 <span class="date">June 2008.</span>
207 The <a href="http://lambdadelta.info/version_1.html#static">
208 HTML pages of the specification of λδ version 1 for Matita 0.5</a>
213 <ul xmlns:ld="http://lambdadelta.info/">
215 <span class="date">May 2008.</span>
216 The specification of λδ version 1 is dismissed.
220 <ul xmlns:ld="http://lambdadelta.info/">
222 <span class="date">March 2008.</span>
223 The specification of λδ version 2 is started with Coq 7.3.1 (false start).
227 <ul xmlns:ld="http://lambdadelta.info/">
229 <span class="date">September 2007.</span>
230 The <a href="http://lambdadelta.info/version_1.html#dynamic">
231 specification of λδ version 1 for Matita 0.4</a>
236 <ul xmlns:ld="http://lambdadelta.info/">
238 <span class="date">November 2006.</span>
239 <a href="http://lambdadelta.info/documentation.html#ldR2">λδ version 1</a>
244 <ul xmlns:ld="http://lambdadelta.info/">
246 <span class="date">December 2005.</span>
247 <a href="http://lambdadelta.info/documentation.html#ldP1">First communication on λδ version 1</a>.
251 <ul xmlns:ld="http://lambdadelta.info/">
253 <span class="date">May 2004.</span>
254 The specification of <a href="http://lambdadelta.info/version_1.html">λδ version 1</a>
255 is started with Coq 7.3.1.
259 <div xmlns:ld="http://lambdadelta.info/" class="head2dx" id="visibility">Visibility <img class="icon37" alt="[spacer]" title="lambdadelta butterfly" src="http://lambdadelta.info/images/b3.png" />
262 <ul xmlns:ld="http://lambdadelta.info/">
264 <span class="date">June 2014.</span>
265 The <a href="http://www.google.com/">Google</a>
266 search for "formal system lambda delta" gives
267 5 resources about λδ in the first 6 results.
271 <ul xmlns:ld="http://lambdadelta.info/">
273 <span class="date">June 2014.</span>
274 The <a href="http://www.yahoo.com/">Yahoo</a>
275 search for "formal system lambda delta" gives
276 4 resources about λδ in the first 5 results.
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306 <div xmlns:ld="http://lambdadelta.info/" class="spacer">Last update: Wed, 10 Sep 2014 14:46:04 +0200</div>