protected WrapIf _if(RVal cond, Runnable body) {
		return new WrapIf(doIf(cond, body));
	}
Generate an "if" statement

<p>
The body is usually a lambda containing additional statements, predicated on this statement's
condition, so that it resembles Java / C syntax:

<pre>
_if(r0.eq(4), () -> {
	r1.set(1);
});
</pre>

<p>
The returned "wrapper" provides for additional follow-on syntax, e.g.:

<pre>
_if(r0.eq(4), () -> {
	r1.set(1);
})._elif(r0.eq(5), () -> {
	r1.set(3);
})._else(() -> {
	r1.set(r0.muli(2));
});
</pre>

@param cond the condition
@param body the body of the statement
@return a wrapper to the generated "if" statement
Ghidra/Features/SystemEmulation/src/main/java/ghidra/pcode/struct/StructuredSleigh.java