String concatenation operator (+)
You can use the string concatenation operator plus symbol (+) only if you use variables and arithmetic expressions in your macro. See Basic and advanced macro format.
You can write a string expression containing multiple concatenations.
The following examples use the string representation required for
the advanced format (see Representation of strings and non-alphanumeric characters).
Expression: Evaluates to:
'Hello ' + 'Fred' + '!' 'Hello Fred!'
'Hi' 'There' (Error, a + operator is required to concatenate strings)
'Hi' + 'There' 'HiThere'