docs: Add ADR for mapping and filtering in expressions

[TomasEng]

Description

This pull request adds an ADR (Architecture Decision Record) that summarises our discussion on mapping and filtering in expressions.

Verification

• No related issues
• Your code builds clean without any errors or warnings
• Manual testing done (required) (tested viewing the document in a Markdown editor)
• Automated testing not relevant; this plull request contains documentation only

Summary by CodeRabbit

Release Notes

• Documentation
  • Added an architectural decision record documenting adoption of mapping and filtering in expressions via the JMESPath standard.
  • Includes decision context, evaluated alternatives with example syntaxes, pros/cons analysis, decision matrix, outcome, and follow-up actions.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

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Reviewing files that changed from the base of the PR and between 73b7748 and 6f73c71.

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• docs/adr/2026-05-11-maps-and-filters-in-expressions.md

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📝 Walkthrough

Walkthrough

This PR adds an ADR that records choosing JMESPath (alternative A6) to enable mapping and filtering in Altinn Studio expressions, describes the problem and twelve decision drivers, documents seven alternatives with examples, evaluates pros/cons, and includes a decision matrix.

Changes

Maps and Filters in Expressions ADR

Layer / File(s)	Summary
ADR metadata, decision and drivers docs/adr/2026-05-11-maps-and-filters-in-expressions.md	Adds ADR title, status, deciders, date, states the chosen result (JMESPath/A6) and initial implementation approach; defines the problem context and lists decision drivers B1–B12.
Alternatives, evaluation and decision matrix docs/adr/2026-05-11-maps-and-filters-in-expressions.md	Documents seven alternatives (A1–A7) with inline and function-style examples for mapping/filtering, provides structured pros/cons for each alternative against drivers, and adds a decision matrix showing JMESPath as the accepted choice.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~5 minutes

Suggested labels

approve

Poem

I hopped through choices, seven wide,
JMESPath chosen, clear my stride,
Maps and filters, lists set free,
The ADR sings—now let it be! 🐇

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely describes the main change: adding an ADR document about mapping and filtering in expressions.
Description check	✅ Passed	The description covers all required sections from the template with sufficient detail and verification checklist items completed.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch adr-for-map-and-filter-in-expressions

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[TomasEng]

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🧹 Nitpick comments (2)

docs/adr/2026-05-11-maps-and-filters-in-expressions.md (2)

25-26: 💤 Low value

Optional: Consider adding a comma for clarity.

The phrase "that is to say not considering memory limits" could be slightly clearer with a comma after "say".

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@docs/adr/2026-05-11-maps-and-filters-in-expressions.md` around lines 25 - 26,
Edit the sentence in the ADR so the parenthetical phrase reads "that is to say,
not considering memory limits" — i.e., insert a comma after "say" in the phrase
"that is to say not considering memory limits" (look for the line containing
"**B3:** It should theoretically (that is to say not considering memory limits)
support...") to improve clarity.

---

30-32: 💤 Low value

Optional: Consider simplifying the intensifier.

The phrase "a very good chance" could be simplified to "a strong likelihood" or similar phrasing for more direct technical writing.

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@docs/adr/2026-05-11-maps-and-filters-in-expressions.md` around lines 30 - 32,
Update the wording for bullet "B7" in the ADR (the line that currently reads
"This might be considered 'nice to have' since there is a very good chance we
will need lambda functions at some point anyway.") to use a more direct
intensifier such as "a strong likelihood" (e.g., replace "a very good chance"
with "a strong likelihood" or similar concise phrasing) so the sentence reads
more technically direct while preserving the original meaning.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@docs/adr/2026-05-11-maps-and-filters-in-expressions.md`:
- Around line 25-26: Edit the sentence in the ADR so the parenthetical phrase
reads "that is to say, not considering memory limits" — i.e., insert a comma
after "say" in the phrase "that is to say not considering memory limits" (look
for the line containing "**B3:** It should theoretically (that is to say not
considering memory limits) support...") to improve clarity.
- Around line 30-32: Update the wording for bullet "B7" in the ADR (the line
that currently reads "This might be considered 'nice to have' since there is a
very good chance we will need lambda functions at some point anyway.") to use a
more direct intensifier such as "a strong likelihood" (e.g., replace "a very
good chance" with "a strong likelihood" or similar concise phrasing) so the
sentence reads more technically direct while preserving the original meaning.

---

ℹ️ Review info

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Configuration used: Path: .coderabbit.yaml

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📥 Commits

Reviewing files that changed from the base of the PR and between c56a34e and 73b7748.

📒 Files selected for processing (1)

• docs/adr/2026-05-11-maps-and-filters-in-expressions.md

[olavsorl]

LGTM! Nice work! 😄