*
* @param operand A non-null value would represent the callsite
* @return The template literal expression
*/
private TemplateLiteralExpressionTree parseTemplateLiteral(ParseTree operand) {
SourcePosition start = operand == null
? getTreeStartLocation()
: operand.location.start;
Token token = nextToken();
ImmutableList.Builder<ParseTree> elements = ImmutableList.builder();
elements.add(new TemplateLiteralPortionTree(token.location, token));