A single-line comment starts with # and extends to the end of the line.
# the answer to everythingmy $x = 42;
Multi-line comments
A multi-line comment starts with #` and followed by the commented text enclosed by bracketing characters (e.g., (), [], {}, 「」, etc.).
#`( Comments beginning with a backtick and one or more opening bracketing characters are embedded comments. They can span more than one line…)my $y = #`{ …or only part of a line. } 3;
Multi-line comments can also be embedded into code.
for#`(each element in) my @array {say#`(or print element) $_ #`(with a newline);}
Using more than one bracketing character lets you include an unmatched close bracket, as shown below.
#`{{ This close curly brace } won't terminate the comment early.}}
Pod comments
=begin commentPod is the successor to Perl 5's POD. This is the simplest way to use it for multi-line comments.For more about Pod, see Pod: https://docs.perl6.org/language/pod=end comment
Pod also provides declarator blocks which are special comments that attach to some source code and can be extracted as documentation. They are either #| or #= and must be immediately followed by either a space or an opening curly brace. In short, blocks starting with #| are attached to the code after them, and blocks starting with #= are attached to the code before them.
#| Compute the distance between two points in the plane.subdistance( Rat \x1, #= First point's abscissa, Rat \y1, #= First point's ordinate, Rat \x2, #= Second point's abscissa, Rat \y2, #= Second point's ordinate, ){returnsqrt((x2 - x1)**2 + (y2 - y1)**2)}