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<meta content="Ferruccio Guidi" name="author">
- <meta content="The formal system lambdadelta" name="description">
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+ <meta content="The formal system λδ" name="description">
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-<a href="http://lambdadelta.info"><img alt="[Crux Logo]"
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-<h1>The Formal System λδ (lambdadelta)<br>
+<a href="http://lambdadelta.info/"><img alt="[Crux Logo]" title="The Crux" src="images/crux_32.png" style="border: 0px solid ; width: 32px; height: 32px;"></a>
+<h1>The Formal System λδ (\lambda\delta)<br>
</h1>
<h2>Towards the unification of terms, types, environments and contexts</h2>
-<img style="width: 95%; height: 4px;" alt="[Separator]"
- title="Separator" src="images/rainbow.png"><br>
-<table
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- border="0" cellpadding="2" cellspacing="20">
+<img style="width: 95%; height: 4px;" alt="[Separator]" title="Separator" src="images/rainbow.png"><br>
+<table style="text-align: left; width: 95%; margin-left: auto; margin-right: auto;" border="0" cellpadding="2" cellspacing="20">
<tbody>
<tr>
<td style="vertical-align: top;">
</ul>
</td>
<td style="vertical-align: top; text-align: left;">
- <h3 style="text-align: right;">Foreword <img
- style="width: 37px; height: 37px;" alt="[Butterfly]" title="Butterfly"
- src="images/b9.png"></h3>
+ <h3 style="text-align: right;">Foreword <img style="width: 37px; height: 37px;" alt="[Butterfly]" title="Butterfly" src="images/b9.png"></h3>
The formal system λδ
-(lambdadelta) is a typed lambda calculus that pursues the static and
+(\lambda\delta) is a typed lambda calculus that pursues the static and
dynamic unification of terms, types, environments and contexts while
-enjoying a well-conceived meta-theory, which includes the commonly
+enjoying a well-conceived theory, which includes the commonly
desired properties.<br>
<br>
λδ takes some features from the calculi of the Automath family and
ζ-contraction and θ-swap. On the other hand,
η-contraction is not included.<br>
<br>
-The meta-theory of λδ includes important properties such as the
+The theory of λδ includes important properties such as the
confluence of reduction, the correctness of types, the
uniqueness of types up to conversion, the subject reduction of the type
assignment, the strong normalization of the typed terms. The
λδ comes in several versions listed in the following table, which
includes the major milestones:<br>
<br>
- <table style="text-align: left; width: 100%;" border="1"
- cellpadding="2" cellspacing="0">
+ <table style="text-align: left; width: 100%;" border="1" cellpadding="2" cellspacing="0">
<tbody>
<tr>
- <td
- style="vertical-align: top; background-color: rgb(223, 223, 223); text-align: center;">Version<br>
+ <td style="vertical-align: top; background-color: rgb(223, 223, 223); text-align: center;">Version<br>
</td>
- <td
- style="vertical-align: top; background-color: rgb(223, 223, 223); text-align: center;">Name<br>
+ <td style="vertical-align: top; background-color: rgb(223, 223, 223); text-align: center;">Name<br>
</td>
- <td
- style="vertical-align: top; background-color: rgb(223, 223, 223); text-align: center;">Started<br>
+ <td style="vertical-align: top; background-color: rgb(223, 223, 223); text-align: center;">Started<br>
</td>
- <td
- style="vertical-align: top; background-color: rgb(223, 223, 223); text-align: center;">Released<br>
+ <td style="vertical-align: top; background-color: rgb(223, 223, 223); text-align: center;">Released<br>
</td>
- <td
- style="vertical-align: top; background-color: rgb(223, 223, 223); text-align: center;">Dismissed<br>
+ <td style="vertical-align: top; background-color: rgb(223, 223, 223); text-align: center;">Dismissed<br>
</td>
</tr>
<tr>
- <td
- style="vertical-align: top; background-color: rgb(255, 223, 191);">2<br>
+ <td style="vertical-align: top; background-color: rgb(255, 223, 191);">2<br>
</td>
- <td
- style="vertical-align: top; background-color: rgb(255, 223, 191);">basic_2<br>
+ <td style="vertical-align: top; background-color: rgb(255, 223, 191);">basic_2<br>
</td>
- <td
- style="vertical-align: top; background-color: rgb(255, 223, 191);">April
+ <td style="vertical-align: top; background-color: rgb(255, 223, 191);">April
2011<br>
</td>
- <td
- style="vertical-align: top; background-color: rgb(255, 223, 191);">planned
+ <td style="vertical-align: top; background-color: rgb(255, 223, 191);">planned
in
2013<br>
</td>
- <td
- style="vertical-align: top; background-color: rgb(255, 223, 191);">not
+ <td style="vertical-align: top; background-color: rgb(255, 223, 191);">not
planned yet<br>
</td>
</tr>
<tr>
- <td
- style="vertical-align: top; background-color: rgb(255, 191, 191);">1<br>
+ <td style="vertical-align: top; background-color: rgb(255, 191, 191);">1<br>
</td>
- <td
- style="vertical-align: top; background-color: rgb(255, 191, 191);">basic_1<br>
+ <td style="vertical-align: top; background-color: rgb(255, 191, 191);">basic_1<br>
</td>
- <td
- style="vertical-align: top; background-color: rgb(255, 191, 191);">May
+ <td style="vertical-align: top; background-color: rgb(255, 191, 191);">May
2004<br>
</td>
- <td
- style="vertical-align: top; background-color: rgb(255, 191, 191);">November
+ <td style="vertical-align: top; background-color: rgb(255, 191, 191);">November
2006<br>
</td>
- <td
- style="vertical-align: top; background-color: rgb(255, 191, 191);">May
+ <td style="vertical-align: top; background-color: rgb(255, 191, 191);">May
2008<br>
</td>
</tr>
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+user <img style="width: 37px; height: 37px;" alt="[Butterfly]" title="Butterfly" src="images/b3.png"></h3>
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-Last update 2012-12-0
1 by <a href="http://www.cs.unibo.it/%7Efguidi/">Ferruccio
+Last update 2012-12-0
2 by <a href="http://www.cs.unibo.it/%7Efguidi/">Ferruccio
Guidi</a><br>
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projects / helm.git / blobdiff