However, C++ lambdas picked the most horrifically ugly syntax possible, and they switch between three subtly different semantics (copy, reference, move) depending on a single glyph. I feel bad for the people working on modern C++ - maintaining backwards compatibility is a huge constraint upon design space.
I'm not surprised that lambdas slow down people that aren't already experienced with them. Since I rarely program in C++, whenever I go back to it, I always have to spend a bit of time bashing my head against the horrific syntax.
It was ugly as heck and was removed as soon as I have c++14
I understand that C++ lambda syntax can be confusing on first encounter, but after reading about them for five minutes it should be very naturally comprehensible to any experienced C++ programmer. It's terse, but very clear.