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22 <div class="head1">The Formal System λδ (\lambda\delta)</div>
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53 The formal system λδ (\lambda\delta) is a typed λ-calculus aiming to support
54 the foundations of Mathematics that require an underlying specification language
55 (for example the <a href="http://www.math.unipd.it/~maietti/">Minimal Type Theory</a>
56 and its predecessors).
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59 λδ is developed in the context of the
60 <a href="http://helm.cs.unibo.it/">Hypertextual Electronic Library of Mathematics</a>
61 as a machine-checked digital specification
62 that is not the formal counterpart of some previously published informal material.
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65 λδ comes in several versions listed in the following table,
66 which includes the major milestones:
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72 <td class="snns component gray">version</td>
73 <td class="snnn component gray">name</td>
74 <td class="snnn component gray">developed with</td>
75 <td class="snnn component gray">started</td>
76 <td class="snnn component gray">announced</td>
77 <td class="snnn component gray">released</td>
78 <td class="ssnn component gray">dismissed</td>
81 <td class="snns orange">2</td>
82 <td class="snnn orange">basic_2</td>
83 <td class="snnn orange">
84 <a href="http://matita.cs.unibo.it/">Matita 0.99.2</a>
86 <td class="snnn orange">April 2011</td>
87 <td class="snnn orange">July 2014</td>
88 <td class="snnn orange">Planned in 2014</td>
89 <td class="ssnn orange">Not planned yet</td>
92 <td class="snss red">1</td>
93 <td class="snsn red">basic_1</td>
95 <a href="http://coq.inria.fr/">Coq 7.3.1</a>
97 <td class="snsn red">May 2004</td>
98 <td class="snsn red">January 2006</td>
99 <td class="snsn red">November 2006</td>
100 <td class="sssn red">May 2008</td>
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142 <div xmlns:ld="http://lambdadelta.info/" class="spacer">Last update: Sun, 06 Jul 2014 17:03:50 +0200</div>