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10 <title>\lambda\delta home page</title>
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22 <div class="head1">The Formal System λδ (\lambda\delta)</div>
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29 <div xmlns:ld="http://lambdadelta.info/" class="text">
30 <table cellpadding="4" cellspacing="0">
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/specification.html">specification</a>
45 <td class="snnn capitalize italic green">
48 <td class="snns capitalize italic green">
49 <a href="http://lambdadelta.info/implementation.html">implementation</a>
51 <td class="ssnn capitalize italic green">
56 <td class="snns capitalize sky">
57 <a href="http://lambdadelta.info/index.html#foreword">foreword</a>
59 <td class="snns capitalize magenta">
60 <a href="http://lambdadelta.info/news.html#milestones">milestones</a>
62 <td class="snns capitalize orange">
63 <a href="http://lambdadelta.info/documentation.html#v2">version 2</a>
65 <td class="snns capitalize green">
66 <a href="http://lambdadelta.info/specification.html#v2">version 2</a>
68 <td class="snnn capitalize 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>
69 <td class="snns capitalize green">
70 <a href="http://lambdadelta.info/implementation.html#lddl">library</a>
72 <td class="ssnn capitalize green">(<a href="http://lambdadelta.info/static/lddl/">static LDDL directory</a>)</td>
75 <td class="snss capitalize sky">
76 <a href="http://lambdadelta.info/index.html#citations">citations</a>
78 <td class="snss capitalize magenta">
79 <a href="http://lambdadelta.info/news.html#visibility">visibility</a>
81 <td class="snss capitalize orange">
82 <a href="http://lambdadelta.info/documentation.html#v1">version 1</a>
84 <td class="snss capitalize green">
85 <a href="http://lambdadelta.info/specification.html#v1">version 1</a>
87 <td class="snsn capitalize green">(<a href="http://lambdadelta.info/static/matita/lambdadelta/">static HELM directory</a>)</td>
88 <td class="snss capitalize green">
89 <a href="http://lambdadelta.info/implementation.html#helena">helena</a>
91 <td class="sssn capitalize green">
98 <!-- ===================================================================== -->
99 <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" />
101 <ul xmlns:ld="http://lambdadelta.info/">
103 <span class="emph gamma">December 2014.</span>
104 <a href="http://lambdadelta.info/implementation.html#v2">"Helena 0.8.2"</a> is released.
107 The corrected specification of Landau's "Grundlagen der Analysis"
108 is validated in λδ version 3.
113 <ul xmlns:ld="http://lambdadelta.info/">
115 <span class="emph gamma">October 2014.</span>
116 <a href="http://lambdadelta.info/documentation.html#ldJ2">λδ version 2A</a>
120 <ul xmlns:ld="http://lambdadelta.info/">
122 <span class="emph beta">July 2014.</span>
123 A new version of this site is online.
126 <ul xmlns:ld="http://lambdadelta.info/">
128 <span class="emph beta">June 2014.</span>
129 <a href="http://lambdadelta.info/documentation.html#ldP8">First communication on λδ version 2.</a>
132 <ul xmlns:ld="http://lambdadelta.info/">
134 <span class="emph alpha">December 2012.</span>
135 The character "_" is removed from the denomination "lambda_delta":
138 The denomination "\lambda\delta" is used in λδ-related texts.
141 The denomination "lambdadelta" is used in λδ-related identifiers.
144 Permanent λδ URL acquired:
145 <a href="http://lambdadelta.info/">http://lambdadelta.info/</a>
146 (pointing at this site).
151 <ul xmlns:ld="http://lambdadelta.info/">
153 <span class="emph alpha">September 2011.</span>
154 The denomination "lambda-delta" changes to "lambda_delta":
157 The character "-" is reserved in λδ textual syntax
158 (recognized by "Helena 0.8.1").
161 Eventually, the occurrences of the character "-"
162 will be replaced by "_" in all λδ-related identifiers.
165 In particular, this refactoring involves file names and path names.
170 <ul xmlns:ld="http://lambdadelta.info/">
172 <span class="emph alpha">April 2011.</span>
173 The specification of <a href="http://lambdadelta.info/version_2.html">λδ version 2</a>
174 and related topics is restarted in
175 <a href="http://matita.cs.unibo.it/">Matita 0.5</a>.
178 <ul xmlns:ld="http://lambdadelta.info/">
180 <span class="emph delta">February 2011.</span>
181 The specification of λδ version 2 with Coq 7.3.1 is abandoned.
184 <ul xmlns:ld="http://lambdadelta.info/">
186 <span class="emph alpha">December 2010.</span>
187 Transient λδ URL acquired: http://lambda-delta.info/ (expires on December 2012).
190 <ul xmlns:ld="http://lambdadelta.info/">
192 <span class="emph beta">November 2010.</span>
193 <a href="http://lambdadelta.info/implementation.html#v1">"Helena 0.8.1"</a> is released.
196 <ul xmlns:ld="http://lambdadelta.info/">
198 <span class="emph beta">September 2009.</span>
199 <a href="http://lambdadelta.info/implementation.html#v0">"Helena 0.8.0"</a> is released and the
200 <a href="http://lambdadelta.info/implementation.html#lddl">λδ Digital Library</a> is started.
203 <ul xmlns:ld="http://lambdadelta.info/">
205 <span class="emph alpha">June 2009.</span>
206 "Helena", a <a href="http://lambdadelta.info/implementation.html#helena">validator for λδ version 2</a>,
207 is available as a part of the <a href="http://helm.cs.unibo.it/">HELM</a> software.
210 <ul xmlns:ld="http://lambdadelta.info/">
212 <span class="emph alpha">September 2008.</span>
216 <ul xmlns:ld="http://lambdadelta.info/">
218 <span class="emph delta">July 2008.</span>
219 <a href="http://lambdadelta.info/documentation.html#ldJ1">First journal paper on λδ</a>
220 accepted for publication.
223 <ul xmlns:ld="http://lambdadelta.info/">
225 <span class="emph delta">July 2008.</span>
226 First <a href="http://helm.cs.unibo.it/procedural/">procedural reconstruction</a>
227 for <a href="http://matita.cs.unibo.it/">Matita 0.5</a>
228 of the λδ version 1 for Coq 7.3.1.
231 <ul xmlns:ld="http://lambdadelta.info/">
233 <span class="emph delta">June 2008.</span>
234 The <a href="http://lambdadelta.info/version_1.html#static">
235 HTML pages of the specification of λδ version 1 for Matita 0.5</a>
239 <ul xmlns:ld="http://lambdadelta.info/">
241 <span class="emph delta">May 2008.</span>
242 The specification of λδ version 1 is concluded.
245 <ul xmlns:ld="http://lambdadelta.info/">
247 <span class="emph alpha">March 2008.</span>
248 The specification of λδ version 2 is started with Coq 7.3.1 (false start).
251 <ul xmlns:ld="http://lambdadelta.info/">
253 <span class="emph gamma">September 2007.</span>
254 The <a href="http://lambdadelta.info/version_1.html#dynamic">
255 specification of λδ version 1 for Matita 0.4</a>
259 <ul xmlns:ld="http://lambdadelta.info/">
261 <span class="emph gamma">November 2006.</span>
262 <a href="http://lambdadelta.info/documentation.html#ldR2">λδ version 1</a>
266 <ul xmlns:ld="http://lambdadelta.info/">
268 <span class="emph beta">December 2005.</span>
269 <a href="http://lambdadelta.info/documentation.html#ldP1">First communication on λδ version 1</a>.
272 <ul xmlns:ld="http://lambdadelta.info/">
274 <span class="emph alpha">May 2004.</span>
275 The specification of <a href="http://lambdadelta.info/version_1.html">λδ version 1</a>
276 is started with Coq 7.3.1.
279 <!-- ===================================================================== -->
280 <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" />
282 <ul xmlns:ld="http://lambdadelta.info/">
284 <span class="emph alpha">June 2014.</span>
285 The <a href="http://www.google.com/">Google</a>
286 search for "formal system lambda delta" gives
287 5 resources about λδ in the first 6 results.
290 <ul xmlns:ld="http://lambdadelta.info/">
292 <span class="emph alpha">June 2014.</span>
293 The <a href="http://www.yahoo.com/">Yahoo</a>
294 search for "formal system lambda delta" gives
295 4 resources about λδ in the first 5 results.
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324 <div xmlns:ld="http://lambdadelta.info/" class="spacer">Last update: Thu, 15 Jan 2015 16:54:44 +0100</div>