A program that uses the $(dollar), variable. : Special Variables « Language Basics « Perl

Perl

1.	Array
2.	CGI
3.	Class
4.	Data Type
5.	Database
6.	File
7.	GUI
8.	Hash
9.	Language Basics
10.	Network
11.	Regular Expression
12.	Report
13.	Statement
14.	String
15.	Subroutine
16.	System Functions
17.	Win32
18.	XML

Java

Java Tutorial

Java Source Code / Java Documentation

Illustrator Tutorials

GIMP Tutorials

C# / C Sharp

C# / CSharp Tutorial

C# / CSharp Open Source

SQL Server / T-SQL Tutorial

Oracle PL / SQL

Oracle PL/SQL Tutorial

Flash / Flex / ActionScript

VBA / Excel / Access / Word

XML

XML Tutorial

Microsoft Office PowerPoint 2007 Tutorial

Microsoft Office Excel 2007 Tutorial

Microsoft Office Word 2007 Tutorial

Perl » Language Basics » Special Variables

A program that uses the $(dollar), variable.


   

#!/usr/local/bin/perl 



$a = "hello"; 

$b = "there"; 

$, = " "; 

$\ = "\n"; 

print ($a, $b);

Related examples in the same category

1.	Special Literals
2.	Splitting up $_
3.	Splitting up $_ and creating an unnamed list
4.	The list separator is a comma
5.	The list separator is the empty string
6.	Passing Arguments at the Command Line
7.	Special Hashes: The %ENV Hash
8.	The %SIG hash sets signal handlers for signals.
9.	A program that changes the value of $/.
10.	A program that uses the $" (dollar and quotation) variable.
11.	A program that uses the $< variable.
12.	A program that uses the $\(dollar and slash) variable.
13.	A simple program that assigns to $_ using .
14.	A simple version of the cat command using $_.
15.	ARGV and the Null Filehandle
16.	ARGV in Perl represents the command-line arguments.
17.	Aliases and Values
18.	Alternative names for Perl system variables.
19.	Assign elements in @_ to scalar
20.	Assign string array to @ARGV by using qw
21.	Assign value to @_
22.	Build the ARGV array with qw function
23.	@_ has runtime scope.
24.	A more expanded version for showing how to use the $_
25.	Built-in variables: $_
26.	Call-by-Reference and the @_ Array
27.	Capturing fatal errors
28.	Catching the sigINT signal
29.	Code the $_ specifically
30.	Compare value entered with number with underscore
31.	Error message is stored in $!
32.	Extracts information from the $] variable.
33.	$! is the error number
34.	$! stores the error message
35.	$" is the separator
36.	$# is the default format
37.	$(dollar), is the separator
38.	$MATCH = $&
39.	$SIG{__DIE__}
40.	$SIG{__WARN__} = 'IGNORE';
41.	$SIG{__WARN__} = sub {die "Warning: $_[0]"};
42.	$\ is 'END_OF_OUTPUT'
43.	$^ is the format header
44.	$^O stores the name of the operating system
45.	$^S: is inside eval
46.	$^W: Check the '-w switch'
47.	$^X: get the Perl execuatable file name
48.	$_ for print function
49.	$_ stores the user input
50.	$~ is the format
51.	%INC values
52.	File-searching program using $ARGV.
53.	Get Computer Name key in the %ENV
54.	Get local time from $^T
55.	If $_contains needle, the string is printed.
56.	Integer signal
57.	Lines Remaining on the Page: $-
58.	List all command line argument
59.	Local builtin var
60.	Locate all numbers less than 6
61.	Manipuate @_ and return @_
62.	Mannually change the $1 variable
63.	Match: $&
64.	Perl 5 Built-In Variables
65.	Perl's modules reside in the directories named in the @INC array, or subdirectories
66.	Perl's special arrays
67.	Perl's special variables
68.	Postmatch $'
69.	Prematch: $`
70.	Print all command line argument
71.	Print the default variable's ($_) value
72.	Quick Sum
73.	Read and set environment variables?
74.	Read lines from supplied filenames
75.	Reference element in @_
76.	Resetting array base
77.	Retrieving the Entire Pattern: $&
78.	Saving in the $& special scalar
79.	Set the $/ and chomp
80.	Special Variables
81.	System variables that control how write sends output to a file
82.	Test of open and die with $!.
83.	The $_ Scalar Variable
84.	The @* field
85.	The @ISA Array and Calling Methods
86.	The Argument Vector @ARGV
87.	The Pattern-Matching Operator and $_
88.	The Substitution Operator and $_
89.	The code executes a line of code you type as long as that line doesn't start with a #
90.	The environment associative array: Associative arrays %ENV holds your system's environment variables.
91.	The following functions and operators work with the $_ variable by default:
92.	The shift operator returns an undefined value if the array has no more elements.
93.	To list all .pm files by using the @INC array
94.	Use while loop to display all entries in ENV
95.	Using $, to set the separator for print command
96.	Using $_ (dollar underscore)
97.	Using $_ as the array index
98.	Using $_ variable with while statement
99.	Using %SIG to define our own signal handlers
100.	Using @_ directly
101.	Using __LINE__ to output line number
102.	Using eof and <> together.
103.	Using the $. variable.
104.	Using the $;(dollar and semicolon) variable.
105.	Using the @_ to reference the parameter
106.	Using the Default Variable $_
107.	Using the diamond operator with @ARGV
108.	Using the if statement to check the command line parameters
109.	Using the special Perl variable $! in the message passed to die.
110.	Using tr to convert all file names passed in to uppercase
111.	Verify the total number of the command line parameter
112.	Working with $_ usually makes programming much easier, but more confusing to the uninitiated
113.	You display the current line of execution in a Perl script by referring to it with the __LINE__ token.
114.	You display the name of the current Perl package with __PACKAGE__.
115.	You display the name of the current file with the __FILE__ token
116.	foreach (@_)
117.	foreach loop and $_
118.	or die $!
119.	or die $^E;
120.	print "Hello, $ENV{USER}!\n";
121.	print $INC{'English.pm'};
122.	print $]; (Perl version number)
123.	print out all pm library location
124.	prints out each element of @ARGV separately
125.	shift: defaults to shifting @ARGV
126.	time - $^T
127.	undef $/;

www.java2java.com | Contact Us

All other trademarks are property of their respective owners.