http://qs321.pair.com?node_id=1231622

pgmer6809 has asked for the wisdom of the Perl Monks concerning the following question:

On Rosetta (https://rosettacode.org/wiki/Continued_fraction#Perl )

there is the perl solution to evaluating Continuous fractions. The code given is: (<===== comments added by me)

```sub continued_fraction {
my (\$a, \$b, \$n) = (@_[0,1], \$_[2] // 100);
#<========= what is \$_[2] // 100 ??

\$a->() + (\$n && \$b->() / continued_fraction(\$a, \$b, \$n-1));
}

printf "&#8730;2  &#8776; %.9f\n", continued_fraction do { my \$n; sub
+{ \$n++ ? 2 : 1 } }, sub { 1 };  # <===== Note there is no third arg p
+assed
printf "e   &#8776; %.9f\n", continued_fraction do { my \$n; sub { \$n++
+ || 2 } }, do { my \$n; sub { \$n++ || 1 } }; # <===== Note there is no
+ third arg passed
printf "&#960;   &#8776; %.9f\n", continued_fraction do { my \$n; sub {
+ \$n++ ? 6 : 3 } }, do { my \$n; sub { (2*\$n++ + 1)**2 } }, 1_000; #<==
+== Here there is a 3rd arg
printf "&#960;/2 &#8776; %.9f\n", continued_fraction do { my \$n; sub {
+ 1/(\$n++ || 1) } }, sub { 1 }, 1_000; #<==== Here there is a 3rd arg