In perl there are two ways to represent string literals: single-quoted strings and double-quoted strings.
Single-Quoted Strings
Single quoted are a sequence of characters that begin and end with a single quote. These quotes are not a part of the string they just mark the beginning and end for the Perl interpreter. If you want a ' inside of your string you need to preclude it with a \ like this \' as you'll see below.
Let's see how this works below.
'four' #has four letters in the string
'can\'t' #has five characters and represents "can't"
'hi\there' #has eight characters and represents"hi\\there" (one \ in the string)
'blah\\blah' #has nine characters and represents "blah\\blah" (one \ in the string)
If you want to put a new line in a single-quoted string it goes something like this
'line1
line2' #has eleven characters line1, newline character, and then line2
Single-quoted strings don't interpret \n as a newline.
Double-Quoted Strings
Double quoted strings act more like strings in C or C++ the
backslash allows you to represent control characters. Another
nice feature Double-Quoted strings offers is variable interpolation
this substitutes the value of a variable into the string. Some examples are below
$word="hello"; #$word becomes hello
$statement="$word world"; #variable interpolation, $statement becomes "hello world"
"Hello World\n"; #"Hello World" followed by a newline
Some of the things you can put in a Double-Quoted String
| Representation | What it Means |
| \a | Bell |
| \b | Backspace |
| \e | Escape |
| \f | Formfeed |
| \n | Newline |
| \r | Return |
| \t | Tab |
| \\ | Backslash |
| \" | Double quote |
| \007 | octal ascii value this time 007 or the bell |
| \x07 | hex ascii value this time 007 or the bell |
| \cD | any control character.. here it is control-D |
| \l | lowercase next letter |
| \u | uppercase next letter |
| \L | lowercase all letters until \E |
| \U | uppercase all letters until \E |
| \Q | Backslash quote all nonletters and nonnumbers until \E |
| \E | Stop \U \L or \Q |
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