Capture This!

[daixtrose]

Overview

• https://www.nextptr.com/tutorial/ta1430524603/capture-this-in-lambda-expression-timeline-of-change

Partially wrong answer from AI

How was https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3424.pdf decided ?

WG21 paper N3424 was reviewed by EWG at the Portland meeting in September 2012.¹²

EWG kept the issue open, rejecting changes to make captured-by-value variables non-const by default (and thus removing mutable). They encouraged Herb Sutter to pursue a follow-up paper on explicit this capture and direct member variable capture to address usability issues with implicit this capture.²

Later Developments
No major changes from N3424's proposals entered C++14; mutable lambdas and implicit this capture remained as in C++11. Explicit *this capture by value arrived in C++17 to enable safer by-value copies of the current object.^{3
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⁂

Footnotes

1. https://stackoverflow.com/questions/5501959/why-does-c11s-lambda-require-mutable-keyword-for-capture-by-value-by-defau ↩

2. https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3736.html ↩ ↩²

3. https://www.nextptr.com/tutorial/ta1430524603/capture-this-in-lambda-expression-timeline-of-change ↩

4. https://www.reddit.com/r/cpp_questions/comments/11u0ebw/rules_for_lambdas_that_capture_this/ ↩

5. https://herbsutter.com/2013/01/01/video-you-dont-know-const-and-mutable/ ↩

6. https://www.reddit.com/r/cpp/comments/1arumja/wg21_aka_c_standard_committee_february_2024/ ↩

7. https://stackoverflow.com/questions/73196817/why-do-lambda-functions-need-to-capture-this-pointer-explicitly-in-c20 ↩

8. https://www.reddit.com/r/cpp/comments/1nswi4s/til_that_the_wg21_wiki_is_still_running_off_a/ ↩

9. https://herbsutter.com/2014/04/03/reader-qa-generic-lambdas/ ↩

10. https://www.reddit.com/r/cpp/comments/1c5voqx/wg21_aka_c_standard_committee_april_2024_mailing/ ↩

11. https://groups.google.com/a/isocpp.org/g/std-proposals/c/Xck6f50kOjU/m/4YmmmVJr89oJ ↩

12. https://www.scribd.com/document/701556710/Lambda-HerbSutter ↩

13. http://jalopezg.dev/2025/06/30/Summer-WG21-Meeting-trip-report/ ↩

14. https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3566.html ↩

15. https://eu.vlex.com/vid/judgment-of-the-court-953652636 ↩

16. https://wg21.link/index.txt ↩

17. https://wg21.link/index.html ↩

18. https://stackoverflow.com/questions/14048919/why-is-mutable-a-lambda-function-attribute-instead-of-being-a-capture-type ↩

19. https://www.fao.org/fao-who-codexalimentarius/committees/ewg/ewg-archive/en/ ↩

[daixtrose]

Some code example for mutable keyword

[daixtrose]

Interesting usage in static ut: https://github.com/qlibs/ut