What does the syntax f.(10) mean?

Ruby
1

In irb I have defined the lambda

f=lambda { |x| x+1 }

and then issued (because I have seen it in someone else code)

f.(10)

which computed 11. But what does the f.(10) syntax mean? It computes the
same as f(10), but why?

2

f.(10) is an alias for f.call(10) - see documentation for Proc#call

f(10) won’t work, you’ve probably meant f[10] as an equivalent method
call.

3

Thank you!