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The Formal Systems of the λδ (\lambda\delta) Family

homenewsspecificationspecification log
forewordmilestonesversion 2(background - syntax - core - applications)
version 2helenaOpen Symbolic Notation (OSN)
citationsvisibilityversion 1(background - core)(static HELM directory)version 1library(static LDDL directory)
Computer-checked formal specifications [butterfly]
The systems of the λδ family are developed as machine-checked digital specifications, and are listed in the next table, which includes the major milestones.
The life cycle of a specification consists of four periods. Alpha: the definitions are designed and the major propositions are proved, then the calculus is announced with a presentation. Beta: major changes and additions may occur before the calculus is released on paper. Gamma: subsequent improvements occur until the specification is completed or superseded, while major changes and additions are announced and reported on paper. Delta: after its conclusion, the specification is modified just for maintenance.
versionnamestagedeveloped withstartedannouncedreleasedconcludedreferences
Version 3"basic_3"J3a
Version 2"basic_2""B"Matita 0.99.4October 2015November 2018November 2019V2b

"A"Matita 0.99.2April 2011June 2014October 2014August 2015V2a   R2c
Ground"ground"Matita 0.99.2August 2011March 2016February 2020
AbandonedCoq 7.3.1March 2008February 2011
Version 1"basic_1""A"Coq 7.3.1May 2004December 2005November 2006May 2008V1a   J1a
Change logs: System and Specification (updated 2019-12).
Informational pages on the specifications are provided.
[butterfly] λδ version 3 (proposed)
The formal specification of λδ version 3 is forthcoming.
[butterfly] λδ version 2 (active)
The formal specification of λδ version 2 is available in the following formats.
Notice: the scripts are checked by the latest version of Matita from HELM Git repository.
[butterfly] λδ version 1 (superseded)
The formal specification of λδ version 1 is available in the following formats.

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Last update: Tue, 22 Dec 2020 18:19:03 +0100