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=== Basic syntax overview ===
=== Basic syntax overview ===
A Perl script or program consists of one or more statements. These statements are simply written in the script in a straightforward fashion. There is no need to have a main() function or anything of that kind.
A Perl script or program consists of one or more statements. These statements are simply written in the script in a straightforward fashion. There is no need to have a <code>main()</code> function or anything of that kind.
Perl statements end in a semi-colon:
Perl statements end in a semi-colon:
print "Hello, world";
[http://perldoc.perl.org/functions/print.html print] "Hello, world";
Comments start with a hash symbol and run to the end of the line
Comments start with a hash symbol and run to the end of the line
Whitespace is irrelevant:
Whitespace is irrelevant:
print
[http://perldoc.perl.org/functions/print.html print]
"Hello, world"
"Hello, world"
;
;
# this would print with a linebreak in the middle
# this would print with a linebreak in the middle
print "Hello
[http://perldoc.perl.org/functions/print.html print] "Hello
world";
world";
Double quotes or single quotes may be used around literal strings:
Double quotes or single quotes may be used around literal strings:
print "Hello, world";
[http://perldoc.perl.org/functions/print.html print] "Hello, world";
print 'Hello, world';
[http://perldoc.perl.org/functions/print.html print] 'Hello, world';
However, only double quotes "interpolate" variables and special characters such as newlines (\n ):
However, only double quotes "interpolate" variables and special characters such as newlines (\n ):
print "Hello, $name\n"; # works fine
[http://perldoc.perl.org/functions/print.html print] "Hello, $name\n"; # works fine
print 'Hello, $name\n'; # prints $name\n literally
[http://perldoc.perl.org/functions/print.html print] 'Hello, $name\n'; # prints $name\n literally
Numbers don't need quotes around them:
Numbers don't need quotes around them:
print 42;
[http://perldoc.perl.org/functions/print.html print] 42;
You can use parentheses for functions' arguments or omit them according to your personal taste. They are only required occasionally to clarify issues of precedence.
You can use parentheses for functions' arguments or omit them according to your personal taste. They are only required occasionally to clarify issues of precedence.
print("Hello, world\n");
[http://perldoc.perl.org/functions/print.html print]("Hello, world\n");
print "Hello, world\n";
[http://perldoc.perl.org/functions/print.html print] "Hello, world\n";
More detailed information about Perl syntax can be found in [http://perldoc.perl.org/perlsyn.html perlsyn].
=== Perl variable types ===
=== Perl variable types ===
