adding basics on ptr vs value receiver

Author: symonk

README.md

@@ -101,3 +101,4 @@ go run . -module closingchannels
 * [79 - Signals](signals/main.go)
 * [80 - Exit](exit/main.go)
 * [81 - ErrGroup](errgroups/main.go)
+* [82 - Pointer Vs Value Receiver](ptr_vs_value_receiver/main.go)

ptr_vs_value_receivers/main.go

@@ -0,0 +1,27 @@
+package ptr_vs_value_receivers
+
+/*
+When to use pointer vs value receiver types is a complicated topic.  In order to fully
+understand it, we need to understand method set(s) and various caveats with mutable
+data (especially slice resizing and allocations etc)
+
+Correctness should always win over speed.
+
+Some guidelines we can follow are:
+
+	* If the receiver is a slice and the method doesn't reslice or reallocate, use a value
+	* If the method needs to mutate the receiver, it must be a pointer
+	* If the receiver is a struct containing unsafe to be copied fields, use a pointer
+	* If the receiver is a large struct or array, a pointer MAY be more efficient (benchmark)
+	* If methods can run concurrently with others that modify the receiver use a value if the
+	changes should not be internally visible to the method, else use a pointer
+	* If the receiver is a struct or array, any of whose elements is a pointer to some mutable,
+	prefer a pointer receiver to make the intention of mutability clear to the reader
+	* When in doubt, use a pointer
+
+
+*/
+
+func Run() {
+
+}