The classic solution of this problem was invented in FORTRAN in early 50 -- it is a backslash at the end of the line. Perl can use #\ as this is pragma to lexical scanner, not the element of the language.

I took a FORTRAN course at Waterloo in Fall of 1976, and at that time the continuation character was a '+' in column 6. I'd like to know which publication or reference told you that a continuation was a backslash at the end of a line.

In addition, I'm quite happy with Perl understanding that a line without a semi-colon is continued on the next line. It's the same rule that C uses, so having ';' as a line terminator has made sense to me since 1981. I'm happy to stick with that convention.