If you need to create an address list that includes previously-seen
addresses you may use the (\fIconcataddr\fR\^) function, which is identical
to (\fIformataddr\fR\^) in all other respects. Note that (\fIconcataddr\fR\^)
-does NOT add addresses to the duplicate-suppression cache.
+does
+.I not
+add addresses to the duplicate-suppression cache.
.SS Other Hints and Tips
Sometimes, the writer of a format function is confused because output is
duplicated. The general rule to remember is simple: If a function or
.fi
.RE
.PP
-Unfortunately, if the Reply-to: header is NOT present, the output line
+Unfortunately, if the Reply-to: header is
+.I not
+present, the output line
will be something like:
.PP
.RS 5
statement (so the rule about not starting with % applies). But the component
escape in our
.B else
-statement (everything after the `%|') is NOT an argument to anything;
+statement (everything after the `%|') is
+.I not
+an argument to anything;
it begins with a %, and thus the value of that component is output.
This also has the side effect of setting the
.I str