Example 2-15. examples/scalars/string_functions_index.p6
#!/usr/bin/perl6
my $s = "The black cat jumped from the green tree";
say index $s, "e"; # 2
say index $s, "e", 3; # 18
say rindex $s, "e"; # 39
say rindex $s, "e", 38; # 38
say rindex $s, "e", 37; # 33