Added docstring for -> (JuliaLang#40470)

Co-authored-by: Fredrik Ekre <[email protected]>

Author: 2 people

base/docs/basedocs.jl

@@ -602,6 +602,32 @@ the last expression in the function body.
 """
 kw"function"
 
+"""
+    x -> y
+
+Create an anonymous function mapping argument(s) `x` to the function body `y`.
+
+```jldoctest
+julia> f = x -> x^2 + 2x - 1
+#1 (generic function with 1 method)
+
+julia> f(2)
+7
+```
+
+Anonymous functions can also be defined for multiple argumets.
+```jldoctest
+julia> g = (x,y) -> x^2 + y^2
+#2 (generic function with 1 method)
+
+julia> g(2,3)
+13
+```
+
+See the manual section on [anonymous functions](@ref man-anonymous-functions) for more details.
+"""
+kw"->"
+
 """
     return