Merge branch 'master' of github.com:MarcusTL12/JuliaKursPVV

2019/Julia/Code/15.lambdas.jl

@@ -0,0 +1,35 @@
+
+# A lambda function is made with an arrow from the arguments
+# to the function body
+f = x -> 2x^2
+@show f(2)
+
+# If the function takes more then one argument, parenthesis are required
+g = (x, y) -> x * y
+@show g(2, 3)
+
+# This also holds for functions taking no arguments
+p = () -> Float64(π)
+@show p()
+
+# Function currying is possible, so if anyone wants to do lambda calculus
+# feel free.
+h = x -> y -> x / y
+@show h(12)(4)
+
+# If a function has to be written over multiple lines, this can be done
+# with a "begin" block.
+fib = n -> begin
+    a, b = 0, 1
+    for i in 1 : n
+        a, b = b, a + b
+    end
+    a
+end
+@show fib.(0:6)
+
+# Lambdas can be useful when passing a function as an argument
+# without wanting to give it a name. Here is an example using a lambda
+# instead of using the do-syntax for file handling
+s = open(io -> String(read(io)), "test.txt", "r")
+println(s)