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POGo receiver methods calling syntax confusion
 

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    <p>I was just reading through <a href="http://golang.org/doc/effective_go.html" rel="nofollow">Effective Go</a> and in the <a href="http://golang.org/doc/effective_go.html#pointers_vs_values" rel="nofollow">Pointers vs. Values</a> section, near the <strong>end</strong> it says:</p> <blockquote> <p>The rule about pointers vs. values for receivers is that value methods can be invoked on pointers and values, but pointer methods can only be invoked on pointers. This is because pointer methods can modify the receiver; invoking them on a copy of the value would cause those modifications to be discarded.</p> </blockquote> <p>To test it, I wrote this:</p> <pre class="lang-go prettyprint-override"><code>package main import ( "fmt" "reflect" ) type age int func (a age) String() string { return fmt.Sprintf("%d yeasr(s) old", int(a)) } func (a *age) Set(newAge int) { if newAge &gt;= 0 { *a = age(newAge) } } func main() { var vAge age = 5 pAge := new(age) fmt.Printf("TypeOf =&gt;\n\tvAge: %v\n\tpAge: %v\n", reflect.TypeOf(vAge), reflect.TypeOf(pAge)) fmt.Printf("vAge.String(): %v\n", vAge.String()) fmt.Printf("vAge.Set(10)\n") vAge.Set(10) fmt.Printf("vAge.String(): %v\n", vAge.String()) fmt.Printf("pAge.String(): %v\n", pAge.String()) fmt.Printf("pAge.Set(10)\n") pAge.Set(10) fmt.Printf("pAge.String(): %v\n", pAge.String()) } </code></pre> <p>And it compiles, even though the document says it shouldn't since the pointer method <code>Set()</code> should not be invocable through the value var <code>vAge</code>. Am I doing something wrong here?</p>
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