#A.19.SOURCE-SET-SPACE-SUBSTRATE:0.1 - What goes wrong if missed

Preface node heading:a-19-source-set-space-substrate-0-1-what-goes-wrong-if-missed:23728

#What this page is

This is generated FPF reference text from the specification preface or supporting sections. It helps interpret FPF; it is not FPF Reference product documentation.

#Methodology

Use it to understand how the specification wants to be read, then return to a route, pattern, or work packet for active work. Cite generated IDs only when the wording changes the task decision.

#Content

If this pattern is missed, authors usually collapse several different things into one vague "space" or one vague "projection":

• the declared source set disappears behind bare words such as front, archive, palette, or portfolio;
• SearchSpaceRef and OutcomeSpaceRef never become explicit, or SpaceRefRelationKind never becomes explicit, so one line silently hides whether search and outcome use one declared space twice or two different declared spaces;
• DescriptorMapRef or DistanceDefRef gets mistaken for the space itself rather than one representation or metric qualifier;
• publication metadata in G.5 or G.10 starts standing in for substrate semantics;
• and distortion, uncertainty, or error is either hidden or treated as if every non-trivial case were only one bridge-loss story.

The result looks tidy, but the reader cannot tell what is being searched, what is being evaluated, what is only being published, and where uncertainty actually enters.

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Last Updated: 2026-06-08 — upstream FPF commit 093d30e8 (github.com/ailev/FPF)