Fixed-point Combinator - Implementing Fixed-point Combinators - Anonymous Recursion By Other Means

Anonymous Recursion By Other Means

Although fixed point combinators are the standard solution for allowing a function not bound to an identifier to call itself, some languages like Perl provide a syntactical construct which allows anonymous functions to refer to themselves. For example, in Perl 5.16 and above, one can write the following:

use feature ":5.16"; sub { my $x = shift; $x == 0 ? 1 : __SUB__->( $x - 1 ); }