for equality.
</p>

<p>
In a case or default clause, the last non-empty statement
may be a (possibly <a href="#Labeled_statements">labeled</a>)
<a href="#Fallthrough_statements">"fallthrough" statement</a> to
indicate that control should flow from the end of this clause to
the first statement of the next clause.
Otherwise control flows to the end of the "switch" statement.

for equality.
</p>

<p>
In a case or default clause, the last non-empty statement
may be a (possibly <a href="#Labeled_statements">labeled</a>)
<a href="#Fallthrough_statements">"fallthrough" statement</a> to
indicate that control should flow from the end of this clause to
the first statement of the next clause.
Otherwise control flows to the end of the "switch" statement.

	}

	context := w.context
	if context == nil {
		context = &build.Default
	}

	// Look in cache.
	// If we've already done an import with the same set
	// of relevant tags, reuse the result.
	var key string
	if usePkgCache {
		if tags, ok := pkgTags[dir]; ok {
			key = tagKey(dir, context, tags)
			if pkg := pkgCache[key]; pkg != nil {
				w.imported[name] = pkg
				return pkg, nil