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19 <img class="icon32" alt="[\lambda\delta home]" title="\lambda\delta home" src="http://lambdadelta.info/images/crux_32.png" />
22 <div class="head1">cic:/matita/lambdadelta/basic_2/ (core λδ version 2)</div>
24 <img class="rule" alt="[Spacer]" title="\lambda\delta rainbow rule" src="http://lambdadelta.info/images/rainbow.png" />
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29 <div xmlns:ld="http://lambdadelta.info/" class="text">
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33 <td class="snns capitalize italic sky">
34 <a href="http://lambdadelta.info/home.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 white">
40 <a href="http://lambdadelta.info/specification.html">specification</a>
42 <td class="snnn capitalize italic white">
45 <td class="snnn capitalize italic white">
48 <td class="snns capitalize italic orange">
49 <a href="http://lambdadelta.info/documentation.html">documentation</a>
51 <td class="snns capitalize italic green">
52 <a href="http://lambdadelta.info/implementation.html">implementation</a>
54 <td class="ssnn capitalize italic green">
59 <td class="snns capitalize sky">
60 <a href="http://lambdadelta.info/home.html#foreword">foreword</a>
62 <td class="snns capitalize magenta">
63 <a href="http://lambdadelta.info/news.html#milestones">milestones</a>
65 <td class="snns capitalize white">
66 <a href="http://lambdadelta.info/specification.html#v2">version 2</a>
68 <td class="snnn capitalize white">(<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="snnn capitalize white">
72 <td class="snns capitalize orange">
73 <a href="http://lambdadelta.info/documentation.html#v2">version 2</a>
75 <td class="snns capitalize green">
76 <a href="http://lambdadelta.info/implementation.html#helena">helena</a>
78 <td class="ssnn capitalize green">
79 <a href="http://lambdadelta.info/osn/">Open Symbolic Notation (OSN)</a>
83 <td class="snss capitalize sky">
84 <a href="http://lambdadelta.info/home.html#citations">citations</a>
86 <td class="snss capitalize magenta">
87 <a href="http://lambdadelta.info/news.html#visibility">visibility</a>
89 <td class="snss capitalize white">
90 <a href="http://lambdadelta.info/specification.html#v1">version 1</a>
92 <td class="snsn capitalize white">(<a href="http://lambdadelta.info/ground_1.html">background</a> - <a href="http://lambdadelta.info/basic_1.html">core</a>)</td>
93 <td class="snsn capitalize white">(<a href="http://lambdadelta.info/static/matita/lambdadelta/">static HELM directory</a>)</td>
94 <td class="snss capitalize orange">
95 <a href="http://lambdadelta.info/documentation.html#v1">version 1</a>
97 <td class="snss capitalize green">
98 <a href="http://lambdadelta.info/implementation.html#lddl">library</a>
100 <td class="sssn capitalize green">(<a href="http://lambdadelta.info/static/lddl/">static LDDL directory</a>)</td>
106 <section>System's Syntax and Behavior</section>
107 <body>This is a summary of the "block structure"
108 of the System's syntactic items and reductions.
110 <table name="basic_2_blk"/>
111 <body>* In terms only.
112 ** In terms and local environments only.
113 *** In global environments only.
114 **** Sort level k in terms only.
117 <div xmlns:ld="http://lambdadelta.info/" class="head2dx" id="summary">Summary of the Specification <img class="icon37" alt="[butterfly]" title="\lambda\delta butterfly" src="http://lambdadelta.info/images/b4.png" />
119 <div xmlns:ld="http://lambdadelta.info/" class="text">Here is a numerical account of the specification's contents
122 <div xmlns:ld="http://lambdadelta.info/" class="text">
123 <table cellpadding="4" cellspacing="0">
126 <td class="snns capitalize italic gray">category</td>
127 <td class="snns italic gray">objects</td>
128 <td class="snnn right italic gray">
131 <td class="snnn italic gray">
134 <td class="snnn right italic gray">
137 <td class="snnn italic gray">
140 <td class="ssnn right italic gray">
145 <td class="snns capitalize italic cyan">sizes</td>
146 <td class="snns italic cyan">files</td>
147 <td class="snnn right italic cyan">205</td>
148 <td class="snns italic cyan">characters</td>
149 <td class="snnn right italic cyan">201104</td>
150 <td class="snns italic cyan">nodes</td>
151 <td class="ssnn right italic cyan">954664</td>
154 <td class="snns capitalize italic green">propositions</td>
155 <td class="snns italic green">theorems</td>
156 <td class="snnn right italic green">61</td>
157 <td class="snns italic green">lemmas</td>
158 <td class="snnn right italic green">706</td>
159 <td class="snns italic green">total</td>
160 <td class="ssnn right italic green">767</td>
163 <td class="snss capitalize italic yellow">concepts</td>
164 <td class="snss italic yellow">declared</td>
165 <td class="snsn right italic yellow">31</td>
166 <td class="snss italic yellow">defined</td>
167 <td class="snsn right italic yellow">74</td>
168 <td class="snss italic yellow">total</td>
169 <td class="sssn right italic yellow">105</td>
174 <div xmlns:ld="http://lambdadelta.info/" class="head3sn" id="B">Stage "B"</div>
175 <ul xmlns:ld="http://lambdadelta.info/">
177 <span class="emph alpha">Ongoing.</span>
178 Context-sensitive subject equivalence
179 for native type assignment.
182 <div xmlns:ld="http://lambdadelta.info/" class="head3sn" id="A2">Stage "A2": "Extending the Applicability Condition"</div>
183 <ul xmlns:ld="http://lambdadelta.info/">
185 <span class="emph alpha">2017 October 16.</span>
186 Exclusion binder in local environments.
187 Ported components: syntax, relocation, s_transition, s_computation, static.
190 <ul xmlns:ld="http://lambdadelta.info/">
192 <span class="emph alpha">2017 April 16.</span>
193 Strong rt-normalization
194 for simply typed terms
195 (anniversary milestone).
198 <ul xmlns:ld="http://lambdadelta.info/">
200 <span class="emph alpha">2017 March 16.</span>
201 First behavioral component reconstructed:
205 <ul xmlns:ld="http://lambdadelta.info/">
207 <span class="emph alpha">2017 February 19.</span>
208 Generic candidates of reducibility.
211 <ul xmlns:ld="http://lambdadelta.info/">
213 <span class="emph alpha">2017 January 17.</span>
214 Confluence for parallel r-transition on referred entries of local environments.
217 <ul xmlns:ld="http://lambdadelta.info/">
219 <span class="emph alpha">2016 September 15.</span>
220 Confluence for context-sensitive parallel r-transition on terms.
223 <ul xmlns:ld="http://lambdadelta.info/">
225 <span class="emph alpha">2016 April 16.</span>
226 Syntactic component reconstructed:
227 syntax, relocation, s_transition, s_computation, static
228 (anniversary milestone).
231 <ul xmlns:ld="http://lambdadelta.info/">
233 <span class="emph alpha">2016 March 25.</span>
234 Relocation with reference transforming maps (rtmap).
237 <ul xmlns:ld="http://lambdadelta.info/">
239 <span class="emph alpha">2015 October 9.</span>
240 λδ version 2A2 is started.
243 <div xmlns:ld="http://lambdadelta.info/" class="head3sn" id="A1">Stage "A1": "Extending the Applicability Condition"</div>
244 <ul xmlns:ld="http://lambdadelta.info/">
246 <span class="emph delta">2015 August 27.</span>
247 λδ version 2A1 appears too complex and is dismissed.
250 <ul xmlns:ld="http://lambdadelta.info/">
252 <span class="emph gamma">2014 October 28.</span>
253 λδ version 2A1 is released.
256 <ul xmlns:ld="http://lambdadelta.info/">
258 <span class="emph beta">2014 September 9.</span>
259 Iterated static type assignment defined (more elegantly)
260 as a primitive notion.
263 <ul xmlns:ld="http://lambdadelta.info/">
265 <span class="emph beta">2014 June 18.</span>
266 Preservation of stratified native validity
267 for context-sensitive computation on terms.
270 <ul xmlns:ld="http://lambdadelta.info/">
272 <span class="emph alpha">2014 June 9.</span>
273 Strong qrst-normalization
274 for simply typed terms.
277 <ul xmlns:ld="http://lambdadelta.info/">
279 <span class="emph alpha">2014 April 16.</span>
280 Lazy equivalence on local environments
281 added as q-step to rst-computation on closures
282 (anniversary milestone).
285 <ul xmlns:ld="http://lambdadelta.info/">
287 <span class="emph alpha">2014 January 20.</span>
288 Parametrized slicing on local environments
289 comprises both versions of this operation
290 (one from basic_1, the other used in basic_2 till now).
293 <ul xmlns:ld="http://lambdadelta.info/">
295 <span class="emph alpha">2013 August 7.</span>
296 Passive support for global environments.
299 <ul xmlns:ld="http://lambdadelta.info/">
301 <span class="emph alpha">2013 July 27.</span>
302 Reaxiomatized β-reductum as in rt-reduction.
305 <ul xmlns:ld="http://lambdadelta.info/">
307 <span class="emph alpha">2013 July 20.</span>
308 Context-sensitive strong rt-normalization
309 for simply typed terms.
312 <ul xmlns:ld="http://lambdadelta.info/">
314 <span class="emph alpha">2013 April 16.</span>
315 Reaxiomatized substitution and reduction
316 commute with respect to subclosure
317 (anniversary milestone).
320 <ul xmlns:ld="http://lambdadelta.info/">
322 <span class="emph alpha">2013 March 16.</span>
323 Mutual recursive preservation of stratified native validity
324 for rst-computation on closures.
327 <ul xmlns:ld="http://lambdadelta.info/">
329 <span class="emph alpha">2012 October 16.</span>
330 Confluence for context-free parallel reduction on closures.
333 <ul xmlns:ld="http://lambdadelta.info/">
335 <span class="emph alpha">2012 July 26.</span>
336 Term binders polarized to control ζ-reduction (not released).
339 <ul xmlns:ld="http://lambdadelta.info/">
341 <span class="emph alpha">2012 April 16.</span>
342 Context-sensitive subject equivalence
343 for atomic arity assignment
344 (anniversary milestone).
347 <ul xmlns:ld="http://lambdadelta.info/">
349 <span class="emph alpha">2012 March 15.</span>
350 Context-sensitive strong normalization
351 for simply typed terms.
354 <ul xmlns:ld="http://lambdadelta.info/">
356 <span class="emph alpha">2012 January 27.</span>
357 Generic candidates of reducibility.
360 <ul xmlns:ld="http://lambdadelta.info/">
362 <span class="emph alpha">2011 September 21.</span>
363 Confluence for context-sensitive parallel reduction on terms.
366 <ul xmlns:ld="http://lambdadelta.info/">
368 <span class="emph alpha">2011 September 6.</span>
369 Confluence for context-free parallel reduction on terms.
372 <ul xmlns:ld="http://lambdadelta.info/">
374 <span class="emph alpha">2011 April 17.</span>
375 λδ version 2 is started.
378 <div xmlns:ld="http://lambdadelta.info/" class="head2dx" id="structure">Logical Structure of the Specification <img class="icon37" alt="[butterfly]" title="\lambda\delta butterfly" src="http://lambdadelta.info/images/b4.png" />
380 <div xmlns:ld="http://lambdadelta.info/" class="text">This table reports the specification's components and their planes.
382 <div xmlns:ld="http://lambdadelta.info/" class="text">
383 <table cellpadding="4" cellspacing="0">
386 <td class="snns top capitalize italic gray">component</td>
387 <td class="snns top italic gray">plane</td>
388 <td class="snns top gray">files</td>
389 <td class="ssnn top gray">
394 <td class="snns top capitalize italic green">static typing</td>
395 <td class="snns top italic green">generic reducibility</td>
396 <td class="snns top green">lsubc ( ? ⊢ ? ⫃[?] ? )</td>
397 <td class="ssnn top green">lsubc_drops lsubc_lsubr lsubc_lsuba</td>
400 <td class="nnns top capitalize italic green">
403 <td class="nnns top italic green">
406 <td class="snns top green">gcp_cr ( ⦃?,?,?⦄ ϵ[?] 〚?〛 )</td>
407 <td class="ssnn top green">gcp_aaa</td>
410 <td class="nnns top capitalize italic green">
413 <td class="nnns top italic green">
416 <td class="snns top green">gcp</td>
417 <td class="ssnn top green">
422 <td class="nnns top capitalize italic green">
425 <td class="snns top italic green">atomic arity assignment</td>
426 <td class="snns top green">lsuba ( ? ⊢ ? ⫃⁝ ? )</td>
427 <td class="ssnn top green">lsuba_drops lsuba_lsubr lsuba_aaa lsuba_lsuba</td>
430 <td class="nnns top capitalize italic green">
433 <td class="nnns top italic green">
436 <td class="snns top green">aaa ( ⦃?,?⦄ ⊢ ? ⁝ ? )</td>
437 <td class="ssnn top green">aaa_drops aaa_fqus aaa_lfdeq aaa_aaa</td>
440 <td class="nnns top capitalize italic green">
443 <td class="snns top italic green">degree-based equivalence on referred entries</td>
444 <td class="snns top green">ffdeq ( ⦃?,?,?⦄ ≡[?,?] ⦃?,?,?⦄ )</td>
445 <td class="ssnn top green">ffdeq_fqup ffdeq_ffdeq</td>
448 <td class="nnns top capitalize italic green">
451 <td class="nnns top italic green">
454 <td class="snns top green">lfdeq ( ? ≡[?,?,?] ? )</td>
455 <td class="ssnn top green">lfdeq_length lfdeq_drops lfdeq_fqup lfdeq_fqus lfdeq_lfdeq</td>
458 <td class="nnns top capitalize italic green">
461 <td class="snns top italic green">generic extension on referred entries</td>
462 <td class="snns top green">lfxs ( ? ⦻*[?,?] ? )</td>
463 <td class="ssnn top green">lfxs_length lfxs_drops lfxs_fqup lfxs_lfxs</td>
466 <td class="nnns top capitalize italic green">
469 <td class="snns top italic green">context-sensitive free variables</td>
470 <td class="snns top green">lsubf ( ⦃?,?⦄ ⫃𝐅* ⦃?,?⦄ )</td>
471 <td class="ssnn top green">lsubf_lsubr lsubf_frees lsubf_lsubf</td>
474 <td class="nnns top capitalize italic green">
477 <td class="nnns top italic green">
480 <td class="snns top green">frees ( ? ⊢ 𝐅*⦃?⦄ ≡ ? )</td>
481 <td class="ssnn top green">frees_drops frees_fqup frees_frees</td>
484 <td class="nnns top capitalize italic green">
487 <td class="snns top italic green">restricted ref. for local env.</td>
488 <td class="snns top green">lsubr ( ? ⫃ ? )</td>
489 <td class="ssnn top green">lsubr_length lsubr_drops lsubr_lsubr</td>
492 <td class="snns top capitalize italic grass">s-computation</td>
493 <td class="snns top italic grass">iterated structural successor for closures</td>
494 <td class="snns top grass">fqus ( ⦃?,?,?⦄ ⊐*[?] ⦃?,?,?⦄ ) ( ⦃?,?,?⦄ ⊐* ⦃?,?,?⦄ )</td>
495 <td class="ssnn top grass">fqus_weight fqus_drops fqus_fqup fqus_fqus</td>
498 <td class="nnns top capitalize italic grass">
501 <td class="nnns top italic grass">
504 <td class="snns top grass">fqup ( ⦃?,?,?⦄ ⊐+[?] ⦃?,?,?⦄ ) ( ⦃?,?,?⦄ ⊐+ ⦃?,?,?⦄ )</td>
505 <td class="ssnn top grass">fqup_weight fqup_drops fqup_fqup</td>
508 <td class="snns top capitalize italic yellow">s-transition</td>
509 <td class="snns top italic yellow">structural successor for closures</td>
510 <td class="snns top yellow">fquq ( ⦃?,?,?⦄ ⊐⸮[?] ⦃?,?,?⦄ ) ( ⦃?,?,?⦄ ⊐⸮ ⦃?,?,?⦄ )</td>
511 <td class="ssnn top yellow">fquq_length fquq_weight</td>
514 <td class="nnns top capitalize italic yellow">
517 <td class="nnns top italic yellow">
520 <td class="snns top yellow">fqu ( ⦃?,?,?⦄ ⊐[?] ⦃?,?,?⦄ ) ( ⦃?,?,?⦄ ⊐ ⦃?,?,?⦄ )</td>
521 <td class="ssnn top yellow">fqu_length fqu_weight</td>
524 <td class="snns top capitalize italic orange">relocation</td>
525 <td class="snns top italic orange">generic slicing for local environments</td>
526 <td class="snns top orange">drops_vector ( ⬇*[?,?] ? ≡ ? ) ( ⬇*[?] ? ≡ ? )</td>
527 <td class="ssnn top orange">
532 <td class="nnns top capitalize italic orange">
535 <td class="nnns top italic orange">
538 <td class="snns top orange">drops ( ⬇*[?,?] ? ≡ ? ) ( ⬇*[?] ? ≡ ? )</td>
539 <td class="ssnn top orange">drops_lstar drops_weight drops_length drops_ext2 drops_lexs drops_lreq drops_drops</td>
542 <td class="nnns top capitalize italic orange">
545 <td class="snns top italic orange">generic relocation</td>
546 <td class="snns top orange">lifts_bind ( ⬆*[?] ? ≡ ? )</td>
547 <td class="ssnn top orange">lifts_weight_bind lifts_lifts_bind</td>
550 <td class="nnns top capitalize italic orange">
553 <td class="nnns top italic orange">
556 <td class="snns top orange">lifts_vector ( ⬆*[?] ? ≡ ? )</td>
557 <td class="ssnn top orange">lifts_lifts_vector</td>
560 <td class="nnns top capitalize italic orange">
563 <td class="nnns top italic orange">
566 <td class="snns top orange">lifts ( ⬆*[?] ? ≡ ? )</td>
567 <td class="ssnn top orange">lifts_simple lifts_weight lifts_tdeq lifts_lifts</td>
570 <td class="nnns top capitalize italic orange">
573 <td class="snns top italic orange">ranged equivalence for local environments</td>
574 <td class="snns top orange">lreq ( ? ≡[?] ? )</td>
575 <td class="ssnn top orange">lreq_length lreq_lreq</td>
578 <td class="nnns top capitalize italic orange">
581 <td class="snns top italic orange">generic entrywise extension</td>
582 <td class="snns top orange">lexs ( ? ⦻*[?,?,?] ? )</td>
583 <td class="ssnn top orange">lexs_length lexs_lexs</td>
586 <td class="snns top capitalize italic red">syntax</td>
587 <td class="snns top italic red">append for local environments</td>
588 <td class="snns top red">append ( ? @@ ? )</td>
589 <td class="ssnn top red">append_length</td>
592 <td class="nnns top capitalize italic red">
595 <td class="snns top italic red">head equivalence for terms</td>
596 <td class="snns top red">theq ( ? ⩳[?,?] ? )</td>
597 <td class="ssnn top red">theq_simple theq_tdeq theq_theq theq_simple_vector</td>
600 <td class="nnns top capitalize italic red">
603 <td class="snns top italic red">degree-based equivalence for terms</td>
604 <td class="snns top red">tdeq ( ? ≡[?,?] ? ) </td>
605 <td class="ssnn top red">tdeq_ext tdeq_tdeq</td>
608 <td class="nnns top capitalize italic red">
611 <td class="snns top italic red">closures</td>
612 <td class="snns top red">cl_weight ( ♯{?,?,?} )</td>
613 <td class="ssnn top red">
618 <td class="nnns top capitalize italic red">
621 <td class="nnns top italic red">
624 <td class="snns top red">cl_restricted_weight ( ♯{?,?} )</td>
625 <td class="ssnn top red">
630 <td class="nnns top capitalize italic red">
633 <td class="snns top italic red">global environments</td>
634 <td class="snns top red">genv</td>
635 <td class="ssnn top red">
640 <td class="nnns top capitalize italic red">
643 <td class="snns top italic red">local environments</td>
644 <td class="snns top red">lenv_ext2</td>
645 <td class="ssnn top red">
650 <td class="nnns top capitalize italic red">
653 <td class="nnns top italic red">
656 <td class="snns top red">lenv_length ( |?| )</td>
657 <td class="ssnn top red">
662 <td class="nnns top capitalize italic red">
665 <td class="nnns top italic red">
668 <td class="snns top red">lenv_weight ( ♯{?} )</td>
669 <td class="ssnn top red">
674 <td class="nnns top capitalize italic red">
677 <td class="nnns top italic red">
680 <td class="snns top red">lenv</td>
681 <td class="ssnn top red">
686 <td class="nnns top capitalize italic red">
689 <td class="snns top italic red">binders for local environments</td>
690 <td class="snns top red">ext2</td>
691 <td class="ssnn top red">ext2_ext2</td>
694 <td class="nnns top capitalize italic red">
697 <td class="nnns top italic red">
700 <td class="snns top red">bind</td>
701 <td class="ssnn top red">bind_weight</td>
704 <td class="nnns top capitalize italic red">
707 <td class="snns top italic red">terms</td>
708 <td class="snns top red">term_vector ( Ⓐ?.? )</td>
709 <td class="ssnn top red">
714 <td class="nnns top capitalize italic red">
717 <td class="nnns top italic red">
720 <td class="snns top red">term_simple ( 𝐒⦃?⦄ )</td>
721 <td class="ssnn top red">
726 <td class="nnns top capitalize italic red">
729 <td class="nnns top italic red">
732 <td class="snns top red">term_weight ( ♯{?} )</td>
733 <td class="ssnn top red">
738 <td class="nnns top capitalize italic red">
741 <td class="nnns top italic red">
744 <td class="snns top red">term</td>
745 <td class="ssnn top red">
750 <td class="nnns top capitalize italic red">
753 <td class="snns top italic red">items</td>
754 <td class="snns top red">item_sd</td>
755 <td class="ssnn top red">
760 <td class="nnns top capitalize italic red">
763 <td class="nnns top italic red">
766 <td class="snns top red">item_sh</td>
767 <td class="ssnn top red">
772 <td class="nnns top capitalize italic red">
775 <td class="nnns top italic red">
778 <td class="snns top red">item</td>
779 <td class="ssnn top red">
784 <td class="nnss top capitalize italic red">
787 <td class="snss top italic red">atomic arities</td>
788 <td class="snss top red">aarity</td>
789 <td class="sssn top red">
797 <img class="rule" alt="[Spacer]" title="\lambda\delta rainbow rule" src="http://lambdadelta.info/images/rainbow.png" />
799 <div xmlns:ld="http://lambdadelta.info/" class="spacer">
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