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intersection_number

Function intersection_number 

Source
pub fn intersection_number(capability: &str) -> u64
Expand description

The Schubert intersection number (codimension) of a capability’s partition — the geometric weight used for rate-limiting capacity.

A capability’s codimension is the sum of its partition parts (the degree of its Schubert cycle). Per Schubert’s rate-limiter, this becomes the per-principal token-bucket capacity multiplier: a principal holding memory:write (codim 2) gets 2× the throughput of one holding memory:read (codim 1); admin (the point class, codim 16) gets 16×. The geometry of access maps to the geometry of throughput.

Coupling: these codimensions mirror policy/policy.toml. If the policy’s partitions change, update this mapping. Unknown capability ids default to codim 1 (the lowest, σ₁) so a future capability is rate-limited conservatively until promoted here.