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4 (* ||A|| A project by Andrea Asperti *)
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15 include "ground/notation/functions/element_i_0.ma".
16 include "ground/relocation/gr_map.ma".
18 (* IDENTITY ELEMENT FOR GENERIC RELOCATION MAPS *****************************)
21 corec definition gr_id: gr_map ≝ ⫯gr_id.
24 "identity element (generic relocation streams)"
27 (* Basic constructions (specific) *******************************************)
30 lemma gr_id_unfold: ⫯𝐢 = 𝐢.
31 <(stream_unfold … (𝐢)) in ⊢ (???%); //