Perl Operators

Pattern Matching		Result
$a =~ /pat/	match	True if $a contains pattern
$a =~ s/p/r/	substitution	Replace contents of p with r in $a
$a =~ tr/a-z/A-Z/	translation	Translate to corresponding characters
Logical Operators		Result
$a && $b	And	True if $a is true and $b is true
$a || $b	Or	$a if $a is true, otherwise $b
! $a	Not	True if $a is not true
Arithmetic Operators		Result
$a + $b	Add	Sum of $a and $b
$a - $b	Subtract	Difference of $a and $b
$a * $b	Multiply	Product of $a times $b
$a / $b	Divide	Quotient of $a divided by $b
$a % $b	Modulus	Remainder of $a divided by $b
$a ** $b	Exponentiate	$a to the power $b
++$a,$a++	Autoincrement	Add 1 to $a
--$a,$a--	Autodecrement	Subtract 1 from $a
rand($a)	Random	A random number in range 0 .. $a
String Operators		Result
$a . $b	Concatenation	Values of $a and $b as one long string
$a x $b	Repeat	Value of $a strung together $b times
substr($a,$o,$l)	Substring	Substring at offset $o of length $l
index($a,$b)	Index	Offset of string $b in string $a
Assignment Operators		Result
$a = $b	Assign	$a gets the value of $b
$a += $b	Add to	Increase $a by $b
$a -= $b	Subtract from	Decrease $a by $b
$a .= $b	Append	Append string $b to $a
File Test Operators		Result
-r $a	Readable	File name in $a is readable by effective uid
-w $a	Writable	Writable by effective uid
-x $a	Executable	Executable by effective uid
-o $a	Owned	Owned by effective uid
-R $a	Readable	Readable by real uid
-W $a	Writable	Writable by real uid
-X $a	Executable	Executable by real uid
-O $a	Owned	Owned by real uid
-e $a	Exists	File exists
-z $a	Non-zero size	File has non-zero size (returns size in bytes)
-s $a	Zero size	File has zero size
-f $a	Regular file	File is a regular file
-d $a	Directory	File is a directory
-l $a	Symbolic link	File is a symbolic link
-p $a	Named pipe	File is a named pipe (FIFO)
-S $a	Socket	File is a socket
-b $a	Block	File is a block special file
-c $a	Character	File is a character special file
-u $a	UID	File has setuid bit set
-g $a	GID	File has setgid bit set
-k $a	Sticky bit	File has sticky bit set
-T $a	Text file	File is a text file
-B $a	Binary	File is a binary file (opposite of -T)
-M $a	Modify	Age of file (at startup) in days since modification
-A $a	Last Access	Age of file (at startup) in days since last access
-C $a	Inode change	Age of file (at startup) in days since inode change