feat(AlgebraicTopology/DoldKan): morphisms which vanishes on degeneracies

[joelriou]

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[github-actions]

PR summary d565667520

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

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Declarations diff

+ DegeneraciesVanish
+ DegeneraciesVanish.comp
+ DegeneraciesVanish.σ_comp
+ degeneraciesVanishPInfty_f
+ degeneraciesVanish_iff_QInfty_f_comp
+ degeneraciesVanish_succ_iff
+ degeneraciesVanish_zero_iff_true

You can run this locally as follows

## summary with just the declaration names:
./scripts/pr_summary/declarations_diff.sh <optional_commit>

## more verbose report:
./scripts/pr_summary/declarations_diff.sh long <optional_commit>

The doc-module for scripts/pr_summary/declarations_diff.sh contains some details about this script.

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Increase in tech debt: (relative, absolute) = (3.00, 0.00)

Current number	Change	Type
6205	3	backward.isDefEq.respectTransparency

Current commit 01648dfb28
Reference commit d565667520

This script lives in the mathlib-ci repository. To run it locally, from your mathlib4 directory:

git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci
../mathlib-ci/scripts/reporting/technical-debt-metrics.sh pr_summary

• The relative value is the weighted sum of the differences with weight given by the inverse of the current value of the statistic.
• The absolute value is the relative value divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).