Departmental Papers (CIS)

Date of this Version


Document Type

Conference Paper


Vilhelm Sjöberg, Chris Casinghino, Ki Yung Ahn, Nathan Collins, Harley D. Eades III, Peng Fu, Garrin Kimmell, Tim Sheard, Aaron Stump, and Stephanie Weirich. Irrelevance, Heterogenous Equality, and Call-by-value Dependent Type Systems. In Fourth workshop on Mathematically Structured Functional Programming (MSFP '12), 2012

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We present a full-spectrum dependently typed core language which includes both nontermination and computational irrelevance (a.k.a. erasure), a combination which has not been studied before. The two features interact: to protect type safety we must be careful to only erase terminating expressions. Our language design is strongly influenced by the choice of CBV evaluation, and by our novel treatment of propositional equality which has a heterogeneous, completely erased elimination form.



Date Posted: 20 July 2012