In Operators§

See primary documentation in context for infix before

multi infix:<before>(Any,       Any)
multi infix:<before>(Real:D,    Real:D)
multi infix:<before>(Str:D,     Str:D)
multi infix:<before>(Version:D, Version:D)

Generic ordering, uses the same semantics as cmp. Returns True if the first argument is smaller than the second.

In StrDistance§

See primary documentation in context for method before

This is actually a class attribute, and called as a method returns the string before the transformation:

say $str-dist.before; # OUTPUT: «fold␤»