String concatenation operatorsString concatenation operators
|These operators concatenate strings.
The syntax is:
<target> .= <right_operand>
<target> << <right_operand>
<target> <, <right_operand>
Operator .= appends <right_operand> to <target>. Operator << appends a space followed by <right_operand> to <target> if <target> is non empty, otherwise sets <target> to <right_operand>. Operator <, is similar to << but uses a comma to separate the two variable contents. The last two operators are useful in creating space-separated or comma-separated lists.