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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">home</a>
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37 <a href="http://lambdadelta.info/news.html">news</a>
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40 <a href="http://lambdadelta.info/documentation.html">documentation</a>
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43 <a href="http://lambdadelta.info/implementation.html">implementation</a>
45 <td class="ssnn component green">
51 <a href="http://lambdadelta.info/index.html#foreword">Foreword</a>
53 <td class="snns magenta">
54 <a href="http://lambdadelta.info/news.html#milestones">Milestones</a>
56 <td class="snns orange">
57 <a href="http://lambdadelta.info/documentation.html#v2">Version 2</a>
59 <td class="snns green">
60 <a href="http://lambdadelta.info/version_2.html">Version 2</a>
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63 <a href="http://lambdadelta.info/ground_2.html">Background</a>
64 <a href="http://lambdadelta.info/basic_2.html">Core</a>
65 <a href="http://lambdadelta.info/apps_2.html">Applications</a>
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76 <a href="http://lambdadelta.info/documentation.html#v1">Version 1</a>
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79 <a href="http://lambdadelta.info/version_1.html">Version 1</a>
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92 The formal system λδ (\lambda\delta) is a typed λ-calculus aiming to support
93 the foundations of Mathematics that require an underlying specification language
94 (for example the <a href="http://www.math.unipd.it/~maietti/">Minimal Type Theory</a>
95 and its predecessors).
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98 λδ is developed in the context of the
99 <a href="http://helm.cs.unibo.it/">Hypertextual Electronic Library of Mathematics</a>
100 as a machine-checked digital specification
101 that is not the formal counterpart of some previously published informal material.
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104 λδ comes in several versions listed in the following table,
105 which includes the major milestones:
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111 <td class="snns component gray">version</td>
112 <td class="snnn component gray">name</td>
113 <td class="snnn component gray">developed with</td>
114 <td class="snnn component gray">started</td>
115 <td class="snnn component gray">announced</td>
116 <td class="snnn component gray">released</td>
117 <td class="ssnn component gray">dismissed</td>
120 <td class="snns orange">2</td>
121 <td class="snnn orange">
122 <a href="http://lambdadelta.info/version_2.html">basic_2</a>
124 <td class="snnn orange">
125 <a href="http://matita.cs.unibo.it/">Matita 0.99.2</a>
127 <td class="snnn orange">April 2011</td>
128 <td class="snnn orange">July 2014</td>
129 <td class="snnn orange">Planned in 2014</td>
130 <td class="ssnn orange">Not planned yet</td>
133 <td class="snss red">1</td>
134 <td class="snsn red">
135 <a href="http://lambdadelta.info/version_1.html">basic_1</a>
137 <td class="snsn red">
138 <a href="http://coq.inria.fr/">Coq 7.3.1</a>
140 <td class="snsn red">May 2004</td>
141 <td class="snsn red">January 2006</td>
142 <td class="snsn red">November 2006</td>
143 <td class="sssn red">May 2008</td>
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150 (revised <span class="date">2012-09</span>).
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189 <div xmlns:ld="http://lambdadelta.info/" class="spacer">Last update: Sun, 20 Jul 2014 11:29:55 +0200</div>