Folds.count([f,] collection; [executor_options...])
Folds.count([f,] collection, executor)
Count the number of true items in collection or items that evaluates to
true by f. Parallel by default.
See Extended help in Folds.reduce for more information.
julia> using Folds
julia> Folds.count([true, true, false])
2
julia> Folds.count(gcd(x, 857142) == 1 for x in 1:10_000_000)
2721603