Tokens are delimited by spaces or special tokens by default. Sometimes
when you use a macro variable reference in combination with other
text, the reference does not resolve as you expect if you simply concatenate
it. Instead, you might need to delimit the reference by adding a period
to the end of it.
A period immediately
following a macro variable reference acts as a delimiter. That is,
a period at the end of a reference forces the macro processor to recognize
the end of the reference. The period does not appear in the resulting
text.