Literal Values
Scalar Values
- Array reference
[1,2,3]
- Code reference
sub {
statements}
- Hash reference
{key1 => val1, key2 => val2,
. . .}
Equivalent to
{key1, val1, key2, val2,
. . .}
.- Numeric
123 1_234 123.4 5E-10 0b010101
(binary)0xff
(hex)0377
(octal)__LINE__
(line number in the current program)- Regular Expression
qr
/string/modifiers- String
'abc'
Literal string, no variable interpolation or escape characters, except
\'
and\\.
"abc"
A string in which variables are interpolated and escape sequences are processed.
`
command`
Evaluates to the output of the command.
Class::
A value that is mostly equivalent to
"Class".
1.2.3 v5.6.0.1
A string (âv-stringâ) composed of the specified ordinals. The ordinal values may be in the Unicode range.
v1.3
is equivalent to"\x{1}\x{3}".
Suitable to be compared to other v-strings using string compare operators.<<
identifierShell-style âhere document.â
__FILE__
The name of the program file.
__PACKAGE__
The name of the current package.
List Values
- (. . .)
(1,2,3)
is a list of three elements.(1,2,3)[0]
is the first element from this list.(1,2,3)[-1]
is the last element.( )
is an empty list.(1..4)
is the same as(1,2,3,4);
likewise('a'..'z').
('a'..'z')[4,7,9]
is a slice of a literal list.- qw
qw/fo br . . . /
is the same as('fo','br', . . . )
.
Hash Values
(. . .)
(key1 => val1, key2 => val2, . . .)
Equivalent to
(key1, val1, key2, val2, . . . )
.
Filehandles
- Predefined filehandles
STDIN, STDOUT, STDERR, ARGV, DATA.
- User-specified filehandles
Any name (identifier without sigil) ...
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