Other lexical members

Identifiers

Identifiers consist of:

• Any letter (or an underscore) present one time.
• Any letter, number or an underscore as all next characters repeated zero or more times.

Identifier examples:

myvar
_default
c9

Strings

Strings consist of:

• Either a single quote (') or double quote ("), called the delimiter.
• Any character except the delimiter (being the first character, a single/double quote) repeated zero or more times.
• The delimiter once again.

Characters inside strings can be escaped with a backslash (\), meaning you can insert the delimiter of the string if you use a backslash (\) to escape it.

List of escaped characters:

• \t: tab
• \n: newline
• \r: carriage return
• \", \': double/single quote.
• \\: backslash.
• \0: null character.

String examples:

"this is a string"
'this is a string too!'
"this string has \"escaped\"\tcharacters!"

Digits

There are three types of digits:

• Decimal digits.
• Hexadecimal digits.
• Binary digits.

Decimal digits

They consist of:

• Any character from 0 to 9 repeated one or more times.
• Optionally, a period (.) followed by any character from 0 to 9 repeated one or more times.

Hexadecimal digits

They consist of:

• The prefix 0x, which can’t change.
• Any character from 0 to 9 and a to f (case insensitive) repeated one or more times.

Binary digits

They consist of:

• The prefix 0b, which can’t change.
• Either 0 or 1 repeated one or more times.

Digit examples:

5
3.14
0x56F
0b1011

Operators, punctuation

Operators can’t be matched by a single expression, as there is a static list of possible operators/punctuation.

All operators supported in C²:

• +
• +=
• ++
• -
• -=
• ->
• *
• *=
• /
• //
• /=
• %
• ^
• =
• ==
• !
• !=
• <
• <=
• >
• >=
• &
• &&
• |
• ||
• ?

All punctuation supported in C²:

• .
• ..
• ...
• (
• )
• {
• }
• [
• ]
• :
• ;
• ,
• #