Added example of chaining of function call

Author: filipsajdak

regression-tests/mixed-ufcs-function-call-starts-chaining.cpp2

@@ -0,0 +1,32 @@
+#include <vector>
+#include <memory>
+
+template <typename T, typename R>
+auto on_scope_exit(T* f, R(*close)(T*)) {
+    return std::unique_ptr<T, decltype(close)>{f, close};
+}
+
+main: () -> int = {
+
+    f2 := fopen("variable2.txt", "w").on_scope_exit(fclose);
+    f2.get().fprintf("you can handle smart_ptrs without changing behaviour of UFCS");
+
+    m := fopen("manual.txt", "w");
+    m.fprintf("Manual handling still works");
+    m.fclose();
+
+/*
+    // When UFCS is modified to extract pointers from smart pointers (when other matches failed)
+    // then below code will work - separate PR prepared
+
+    f := fopen("variable.txt", "w").on_scope_exit(fclose);
+    f.fprintf("This one use variable and\n");
+    f.fprintf("    separate\n");
+    f.fprintf("        calls\n");
+    f.fprintf("            of fprintfs");
+
+    fopen("one_liner.txt", "w").on_scope_exit(fclose)
+                               .fprintf("This is oneliner!!\n\nAnd it just close automatically");
+*/
+
+}