}
</pre>

<p>
That is, the compiler must not rewrite the program into this one:
</p>

<pre>
*p = 2
if !cond {
	*p = 1
}
</pre>

<p>
If <code>cond</code> is false and another goroutine is reading <code>*p</code>,
then in the original program, the other goroutine can only observe any prior value of <code>*p</code> and <code>1</code>.

	printString("type is bool or string")  // type of i is type of x (interface{})
default:
	printString("don't know the type")     // type of i is type of x (interface{})
}
</pre>

<p>
could be rewritten:
</p>

<pre>
v := x  // x is evaluated exactly once
if v == nil {
	i := v                                 // type of i is type of x (interface{})
	printString("x is nil")

those strings cannot be used directly as identifier names.
Instead, the assembler allows the middle dot character U+00B7
and the division slash U+2215 in identifiers and rewrites them to
plain period and slash.
Within an assembler source file, the symbols above are written as
<code>fmt·Printf</code> and <code>math∕rand·Int</code>.

	printString("type is bool or string")  // type of i is type of x (interface{})
default:
	printString("don't know the type")     // type of i is type of x (interface{})
}
</pre>

<p>
could be rewritten:
</p>

<pre>
v := x  // x is evaluated exactly once
if v == nil {
	i := v                                 // type of i is type of x (interface{})
	printString("x is nil")