Welcome

StockholmCpp #64

Today’s sponsor

C++ news

C++26 DIS voting still open (until Oct.)

C++ news

Bjarne Stroustrup,Profiles for Simplicity and Guarantees - CppCon 2026

I like contracts, but I think the C++26 contracts are awful and I am not sure if they are useful in this context (1:06:38)

C++ news

September mailing list is here

P2688R6, Pattern Matching with match and case
P4444R0, std::big_int
P4381R0, Chairing SG21 and then objecting to Contracts

https://wg21.org/mailing/?mailing=2026-09
https://wg21.link/{papernumber}

TK611/AG09

Round table with 4 international guests

3 year cadence is outdated

=> We need something faster

TK611/AG09

Usual topic discussion
3 year cadence is outdated

⇒ We need something faster

3 years train was good 2011, less good 2026

TK611/AG09

⇒ We need something faster

Paper > WhitePaper (was TS) > Implementation
> Standard

Possibilities
Paper suggesting change
WG21 open for suggestion

SwedenCpp News

28 Sep. 2016, @Tritech (now part of Prevas)

SwedenCpp News

StockholmCpp Planning 2026

October 22
End of November (Open for new event host!)

2027 planning has started

SwedenCpp News

Nobody supports SwedenCpp
but you can change that

https://buymeacoffee.com/swedencpp

SwedenCpp News

The C++ content hub!

X and Bsky get a daily reminder to visit us

Call for Papers!

A community from the community for the community

Submit your ideas and suggestions

Call for Papers!

You know how it works

Quiz time

Quiz time

bool is_even(int n) {
  return n % 2 == 0;
} // best and fastest ever, can't rewrite

int main() {
  std::vector<int> v{1, 2, 3, 4, 5, 6, 7};
  // want reuse, but the other way around
  auto is_odd = std::______(is_even);

  auto odd_count = std::count_if(v.begin(), v.end(),
                                is_odd);
  std::print("odd_count = {}", odd_count);  // odd_count = 4
}

Quiz time

bool is_even(int n) {
  return n % 2 == 0;
}

int main() {
  std::vector<int> v{1, 2, 3, 4, 5, 6, 7};

  auto is_odd = std::not_fn(is_even);

  auto odd_count = std::count_if(v.begin(), v.end(),
                                is_odd);
  std::print("odd_count = {}", odd_count);  // odd_count = 4
}

std::not_fn, C++-17

Today’s program

Arno: Linux shared libraries
🍹 🍕 Mingle 🍕 🍻
Jean: C++ Memory safety for safety-critical
and non-safety critical applications.

Väl mött!