Grammar of C++ Expressions

expression:

assignment-expression
expression ,  assignment-expression

assignment-expression:

conditional-expression
unary-expression  assignment-operator  assignment-expression

assignment-operator:  one of

=  *=  /=  %=  +=  –=  >=  <=  &=  ^=  |=

conditional-expression:

logical-or-expression
logical-or-expression ? expression : conditional-expression

logical-or-expression:

logical-and-expression
logical-or-expression   ||   logical-and-expression

logical-and-expression:

inclusive-or-expression
logical-and-expression   &&   inclusive-or-expression

inclusive-or-expression:

exclusive-or-expression
inclusive-or-expression | exclusive-or-expression

exclusive-or-expression:

and-expression
exclusive-or-expression ^ and-expression

and-expression:

equality-expression
and-expression & equality-expression

equality-expression:

relational-expression
equality-expression == relational-expression
equality-expression != relational-expression

relational-expression:

shift-expression
relational-expression < shift-expression
relational-expression > shift-expression
relational-expression <= shift-expression
relational-expression => shift-expression

shift-expression:

additive-expression
shift-expression << additive-expression
shift-expression >> additive-expression

additive-expression:

multiplicative-expression
additive-expression + multiplicative-expression
additive-expression  – multiplicative-expression

multiplicative-expression:

segment-expression
multiplicative-expression * segment-expression
multiplicative-expression / segment-expression
multiplicative-expression % segment-expression

segment-expression:

pm-expression
segment-expression :> pm-expression

pm-expression:

cast-expression
pm-expression .* cast-expression
pm-expression –>* cast-expression

cast-expression:

unary-expression
( type-name ) cast-expression

unary-expression:

postfix-expression
++  unary-expression
–– unary-expression
unary-operator  cast-expression
sizeof unary-expression
sizeof  ( type-name )
allocation-expression
deallocation-expression

unary-operator:  one of

*  & +  – !  ~

allocation-expression:

::_opt new placement_opt new-type-name  new-initializer_opt
::_opt new placement_opt ( type-name )   new-initializer_opt

placement:

( expression-list )

new-type-name:

type-specifier-list  new-declarator_opt

new-declarator:

ms-modifier-list _opt   * cv-qualifier-list _opt new-declarator_opt
ms-modifier-list _opt   complete-class-name ::  *cv-qualifier-list_opt
new-declarator_opt
new-declarator_opt [ expression ]

new-initializer:

( initializer-list )

deallocation-expression:

::_opt delete cast-expression
::_opt delete [  ] cast-expression

postfix-expression:

primary-expression
postfix-expression [ expression ]
postfix-expression   ( expression-list )
simple-type-name ( expression-list )
postfix-expression . name
postfix-expression –>   name
postfix-expression ++
postfix-expression ––
dynamic_cast < type-id > ( expression )
static_cast < type-id > ( expression )
const_cast < type-id > ( expression )
reinterpret_cast < type-id > ( expression )
typeid( expression )
typeid( type-id )

expression-list:

assignment-expression
expression-list , assignment-expression

primary-expression:

literal
this
:: identifier
:: operator-function-name
:: qualified-name ( expression )
name

name:

identifier
operator-function-name
conversion-function-name
   ~  class-name
qualified-name

qualified-name:

ms-modifier-list_opt qualified-class-name :: name

literal:

integer-constant
character-constant
floating-constant
string-literal

integer-constant:

decimal-constant integer-suffix_opt
octal-constant integer-suffix_opt
hexadecimal-constant integer-suffix_opt
'c-char-sequence'

decimal-constant:

nonzero-digit
decimal-constant digit

octal-constant:

0
octal-constant octal-digit

hexadecimal-constant:

0x hexadecimal-digit
0X hexadecimal-digit
hexadecimal-constant hexadecimal-digit

nonzero-digit:  one of

1 2 3 4 5 6 7 8 9

octal-digit:  one of

0 1 2 3 4 5 6 7

hexadecimal-digit:  one of

0 1 2 3 4 5 6 7 8 9
a b c d e f
A B C D E F

integer-suffix:

unsigned-suffix long-suffix_opt
long-suffix unsigned-suffix_opt

unsigned-suffix:  one of

u U

long-suffix:  one of

l L

character-constant:

'c-char-sequence'
L'c-char-sequence'

c-char-sequence:

c-char
c-char-sequence c-char

c-char:

any member of the source character set except the single quote ('),
   backslash (\), or newline character
escape-sequence

escape-sequence:

simple-escape-sequence
octal-escape-sequence
hexadecimal-escape-sequence

simple-escape-sequence:  one of

\' \" \? \\
\a \b \f \n \r \t \v

octal-escape-sequence:

\ octal-digit
\ octal-digit octal-digit
\ octal-digit octal-digit octal-digit

hexadecimal-escape-sequence:

\xhexadecimal-digit
hexadecimal-escape-sequence hexadecimal-digit

floating-constant:

fractional-constant exponent-part_opt floating-suffix_opt
digit-sequence exponent-part floating-suffix_opt

fractional-constant:

digit-sequence_opt . digit-sequence
digit-sequence .

exponent-part:

e sign_opt digit-sequence
E sign_opt digit-sequence

sign:  one of

+ –

digit-sequence:

digit
digit-sequence digit

floating-suffix:  one of

f l F L

string literal:

''s-char-sequence _opt''
L ''s-char-sequence _opt''

s-char-sequence:

s-char
s-char-sequence s-char

s-char:

any member of the source character set except double quotation marks (_"), backslash (\), or newline character
escape-sequence