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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="ssns capitalize italic green">
49 <a href="http://lambdadelta.info/implementation.html">implementation</a>
53 <td class="snns capitalize sky">
54 <a href="http://lambdadelta.info/index.html#foreword">foreword</a>
56 <td class="snns capitalize magenta">
57 <a href="http://lambdadelta.info/news.html#milestones">milestones</a>
59 <td class="snns capitalize orange">
60 <a href="http://lambdadelta.info/documentation.html#v2">version 2</a>
62 <td class="snns capitalize green">
63 <a href="http://lambdadelta.info/specification.html#v2">version 2</a>
65 <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>
66 <td class="ssns capitalize green">
67 <a href="http://lambdadelta.info/implementation.html#lddl">library</a>
71 <td class="snss capitalize sky">
72 <a href="http://lambdadelta.info/index.html#citations">citations</a>
74 <td class="snss capitalize magenta">
75 <a href="http://lambdadelta.info/news.html#visibility">visibility</a>
77 <td class="snss capitalize orange">
78 <a href="http://lambdadelta.info/documentation.html#v1">version 1</a>
80 <td class="snss capitalize green">
81 <a href="http://lambdadelta.info/specification.html#v1">version 1</a>
83 <td class="snsn capitalize green">
86 <td class="ssss capitalize green">
87 <a href="http://lambdadelta.info/implementation.html#helena">helena</a>
96 <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" />
99 <ul xmlns:ld="http://lambdadelta.info/">
101 <span class="emph beta">July 2014.</span>
102 A new version of this site is online.
106 <ul xmlns:ld="http://lambdadelta.info/">
108 <span class="emph beta">June 2014.</span>
109 <a href="http://lambdadelta.info/documentation.html#ldP8">First communication on λδ version 2.</a>
113 <ul xmlns:ld="http://lambdadelta.info/">
115 <span class="emph alpha">December 2012.</span>
116 The character "_" is removed from the denomination "lambda_delta":
119 The denomination "\lambda\delta" is used in λδ-related texts.
122 The denomination "lambdadelta" is used in λδ-related identifiers.
125 Permanent λδ URL acquired:
126 <a href="http://lambdadelta.info/">http://lambdadelta.info/</a>
127 (pointing at this site).
133 <ul xmlns:ld="http://lambdadelta.info/">
135 <span class="emph alpha">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.
153 <ul xmlns:ld="http://lambdadelta.info/">
155 <span class="emph alpha">April 2011.</span>
156 The specification of <a href="http://lambdadelta.info/version_2.html">λδ version 2</a>
157 and related topics is restarted in
158 <a href="http://matita.cs.unibo.it/">Matita 0.5</a>.
162 <ul xmlns:ld="http://lambdadelta.info/">
164 <span class="emph delta">February 2011.</span>
165 The specification of λδ version 2 with Coq 7.3.1 is abandoned.
169 <ul xmlns:ld="http://lambdadelta.info/">
171 <span class="emph alpha">December 2010.</span>
172 Transient λδ URL acquired: http://lambda-delta.info/ (expires on December 2012).
176 <ul xmlns:ld="http://lambdadelta.info/">
178 <span class="emph beta">November 2010.</span>
179 "Helena 0.8.1" is released.
183 <ul xmlns:ld="http://lambdadelta.info/">
185 <span class="emph beta">September 2009.</span>
186 "Helena 0.8.0" is released and the
187 <a href="http://lambdadelta.info/implementation.html#lddl">λδ Digital Library</a>
192 <ul xmlns:ld="http://lambdadelta.info/">
194 <span class="emph alpha">June 2009.</span>
195 "Helena", a <a href="http://lambdadelta.info/implementation.html#helena">validator for λδ version 2</a>,
196 is available as a part of the <a href="http://helm.cs.unibo.it/">HELM</a> software.
200 <ul xmlns:ld="http://lambdadelta.info/">
202 <span class="emph alpha">September 2008.</span>
207 <ul xmlns:ld="http://lambdadelta.info/">
209 <span class="emph delta">July 2008.</span>
210 <a href="http://lambdadelta.info/documentation.html#ldJ1">First journal paper on λδ</a>
211 accepted for publication.
215 <ul xmlns:ld="http://lambdadelta.info/">
217 <span class="emph delta">July 2008.</span>
218 First <a href="http://helm.cs.unibo.it/procedural/">procedural reconstruction</a>
219 for <a href="http://matita.cs.unibo.it/">Matita 0.5</a>
220 of the λδ version 1 for Coq 7.3.1.
224 <ul xmlns:ld="http://lambdadelta.info/">
226 <span class="emph delta">June 2008.</span>
227 The <a href="http://lambdadelta.info/version_1.html#static">
228 HTML pages of the specification of λδ version 1 for Matita 0.5</a>
233 <ul xmlns:ld="http://lambdadelta.info/">
235 <span class="emph delta">May 2008.</span>
236 The specification of λδ version 1 is concluded.
240 <ul xmlns:ld="http://lambdadelta.info/">
242 <span class="emph alpha">March 2008.</span>
243 The specification of λδ version 2 is started with Coq 7.3.1 (false start).
247 <ul xmlns:ld="http://lambdadelta.info/">
249 <span class="emph gamma">September 2007.</span>
250 The <a href="http://lambdadelta.info/version_1.html#dynamic">
251 specification of λδ version 1 for Matita 0.4</a>
256 <ul xmlns:ld="http://lambdadelta.info/">
258 <span class="emph gamma">November 2006.</span>
259 <a href="http://lambdadelta.info/documentation.html#ldR2">λδ version 1</a>
264 <ul xmlns:ld="http://lambdadelta.info/">
266 <span class="emph beta">December 2005.</span>
267 <a href="http://lambdadelta.info/documentation.html#ldP1">First communication on λδ version 1</a>.
271 <ul xmlns:ld="http://lambdadelta.info/">
273 <span class="emph alpha">May 2004.</span>
274 The specification of <a href="http://lambdadelta.info/version_1.html">λδ version 1</a>
275 is started with Coq 7.3.1.
281 <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" />
284 <ul xmlns:ld="http://lambdadelta.info/">
286 <span class="emph alpha">June 2014.</span>
287 The <a href="http://www.google.com/">Google</a>
288 search for "formal system lambda delta" gives
289 5 resources about λδ in the first 6 results.
293 <ul xmlns:ld="http://lambdadelta.info/">
295 <span class="emph alpha">June 2014.</span>
296 The <a href="http://www.yahoo.com/">Yahoo</a>
297 search for "formal system lambda delta" gives
298 4 resources about λδ in the first 5 results.
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328 <div xmlns:ld="http://lambdadelta.info/" class="spacer">Last update: Tue, 04 Nov 2014 16:28:51 +0100</div>