[Merged by Bors] - feat: measurability of positive and negative parts

[kebekus]

Provide fun_prop lemmas for the measurability of positive and negative parts.

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[github-actions]

PR summary ebb592349d

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

+ AEMeasurable.leOnePart
+ AEMeasurable.oneLePart
++ leOnePart
++ oneLePart

You can run this locally as follows

## from your `mathlib4` directory:
git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci

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

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

The doc-module for scripts/pr_summary/declarations_diff.sh in the mathlib-ci repository contains some details about this script.

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No changes to strong technical debt.

No changes to weak technical debt.

Current commit ebb592349d
Reference commit 6da0491965

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).

[RemyDegenne]

Thanks!
bors d+

[mathlib-bors]

✌️ kebekus can now approve this pull request until 2026-06-18 14:34 UTC (in 2 weeks). To approve and merge, reply with bors r+. More detailed instructions are available here.

[RemyDegenne]

Sorry I meant to merge:
bors r+

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

• ci (staging) / Lint style
• ci (staging) / Post-Build Step
• ci (staging) / Post-CI job
• ci (staging) / Build

[kebekus]

@RemyDegenne Thanks! And good to be hearing from you.