chapter 2 done

learning_go/2_generic_types_and_declarations/README.md

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+# 2_generic_types_and_declarations
+
+* 5 types of literals in Go: 
+    * integer
+    * floating-point
+    * rune
+    * string
+    * complex
+
+* differences between `var` and `:=`:
+    * `var` - declares a variable, but does not initialize it
+    * `:=` - declares and initializes a variable
+* more subtle: `:=` should (and can) only be used inside function body, while `var` also works on package-level (though, it's rare to declare variable like this - declarations list should then be used)
+* sometimes `:=` shouldn't be used inside function body (e.g. when you want to declare a variable with the same name as a package-level variable) to make your intention clear
+* `const` - declares a constant, which must be initialized at the time of declaration
+* `namingConvention`: 
+    * `PascalCase` - for exported names (visible outside of package)
+    * `camelCase` - for internal names (visible only inside package)
+    * no `snake_case` in Go as in Python