#A.19.SOURCE-SET-SPACE-SUBSTRATE:2 - Problem

Preface node heading:a-19-source-set-space-substrate-2-problem:24383

#What this page is

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#Methodology

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#Content

How should one declare a source-set and search/outcome-space line so that:

1. the declared source set remains explicit and recoverable;
2. SearchSpaceRef and OutcomeSpaceRef stay guarded refs to declared A.19 CharacteristicSpace, not new free-floating space kinds;
3. the text states whether those refs point to one declared space or to two distinct declared spaces;
4. the source-to-outcome relation is explicit enough for the reader to know which source-to-outcome relation mode is being claimed: mapped, projected, translated, scored, or otherwise connected;
5. distortion, uncertainty, and error are stated honestly rather than hidden in prose;
6. SourceSetComposition and DerivedViewKind remain conditional fields rather than fabricated mandatory baggage;
7. qualifier refs such as OutcomeMapRef, SpaceMetricRef, TransitionRelationRef, and BridgeDistortionNote remain available but substrate-side only;
8. and neighboring declarations such as A.19, C.18, G.5, G.10, and A.19.DECLARED-SUBSTRATE-INTERPRETIVE-VIEW can dock to the substrate without redefining it?

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Last Updated: 2026-06-17 — upstream FPF commit 646b0b9b (github.com/ailev/FPF)