The Evolutions of Lambdas in C++14, C++17 and C++20
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The Evolutions of Lambdas in C++14, C++17 and C++20
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Re: The Evolutions of Lambdas in C++14, C++17 and C++20
#2C++23 drop the word auto?
myLambda = [](&&x){ std::cout Re: The Evolutions of Lambdas in C++14, C++17 and C++20
#3C++23 drop the word auto? myLambda = [](&&x){ std::cout what's the point of having to write auto everywhere
syntactical disambiguation, there's already something called "the most vexing parse". C++ is full of little holes like these and getting rid of auto would surely at least double compile times or at worst make parsing C++ actually impossible.
Re: The Evolutions of Lambdas in C++14, C++17 and C++20
#4C++23 drop the word auto? myLambda = [](&&x){ std::cout what's the point of having to write auto everywhere
Problem is, function parameter names are optional, so you can already have something like `[](x){}`, where `x` is a type.
Re: The Evolutions of Lambdas in C++14, C++17 and C++20
#5C++23 drop the word auto? myLambda = [](&&x){ std::cout what's the point of having to write auto everywhere
As seen from Python vs Lua: without a keyword for introduction it's less clear which scope a variable belongs to. Scopes are part of deterministic destruction in C++ and should not be taken lightly.
As a general preference, I'd always want a keyword to introduce a new variable, and most languages seem to agree even if they didn't have to.
Re: The Evolutions of Lambdas in C++14, C++17 and C++20
#6Template lambdas is in my opinion the most useful evolution and has been a long time coming. I figure it was held back by template haters who want terse syntax and don't understand how it's much more powerful than auto/concepts.
I wouldn't say it's a smaller evolution than previous iterations.
Re: The Evolutions of Lambdas in C++14, C++17 and C++20
#7C++23 drop the word auto? myLambda = [](&&x){ std::cout what's the point of having to write auto everywhere
syntactical disambiguation, there's already something called "the most vexing parse". C++ is full of little holes like these and getting rid of auto would surely at least double compile times or at worst make parsing C++ actually impossible.
That is what happens when a language makes the compromise to be copy-paste compatible with https://cdecl.org/
Re: The Evolutions of Lambdas in C++14, C++17 and C++20
#8C++23 drop the word auto? myLambda = [](&&x){ std::cout what's the point of having to write auto everywhere
As seen from Python vs Lua: without a keyword for introduction it's less clear which scope a variable belongs to. Scopes are part of deterministic destruction in C++ and should not be taken lightly. As a general preference, I'd always want a keyword to introduce a new variable, and most languages seem to agree even if they didn't have to.
In this case x must obviously be in a new scope as all function parameters. There isn't possibly be an ambiguity here.
Re: The Evolutions of Lambdas in C++14, C++17 and C++20
#9Regarding returning lambdas, of course it could be done even in c++11 via std::function.
Re: The Evolutions of Lambdas in C++14, C++17 and C++20
#10Earlier quoted context omitted.
As seen from Python vs Lua: without a keyword for introduction it's less clear which scope a variable belongs to. Scopes are part of deterministic destruction in C++ and should not be taken lightly. As a general preference, I'd always want a keyword to introduce a new variable, and most languages seem to agree even if they didn't have to.
In this case x must obviously be in a new scope as all function parameters. There isn't possibly be an ambiguity here.
I think grandparent is referring to myLambda - that could be a new variable or overwriting of an existing one.
I agree with them, in Python the number of times something like this happens:
myVariable = 10
myVariablr = clever_function(myVariable)