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[stmt.ranged]

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  ### The range-based `for` statement <a id="stmt.ranged">[[stmt.ranged]]</a>
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- For a range-based `for` statement of the form
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  ``` bnf
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- 'for (' for-range-declaration : expression ')' statement
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  ```
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- let *range-init* be equivalent to the *expression* surrounded by
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- parentheses[^2]
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-
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- ``` bnf
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- '(' expression ')'
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- ```
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-
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- and for a range-based `for` statement of the form
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-
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- ``` bnf
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- 'for' '(' for-range-declaration ':' braced-init-list ')' statement
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- ```
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-
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- let *range-init* be equivalent to the *braced-init-list*. In each case,
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- a range-based `for` statement is equivalent to
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-
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- ``` cpp
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- {
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- auto && __range = range-init;
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- for ( auto __begin = begin-expr,
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- __end = end-expr;
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- __begin != __end;
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- ++__begin ) {
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- for-range-declaration = *__begin;
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- statement
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- }
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- }
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- ```
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-
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- where `__range`, `__begin`, and `__end` are variables defined for
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- exposition only, and `_RangeT` is the type of the *expression*, and
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- *begin-expr* and *end-expr* are determined as follows:
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-
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- - if `_RangeT` is an array type, *begin-expr* and *end-expr* are
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- `__range` and `__range + __bound`, respectively, where `__bound` is
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- the array bound. If `_RangeT` is an array of unknown size or an array
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- of incomplete type, the program is ill-formed;
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- - if `_RangeT` is a class type, the *unqualified-id*s `begin` and `end`
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- are looked up in the scope of class `\mbox{_RangeT}` as if by class
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- member access lookup ([[basic.lookup.classref]]), and if either (or
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- both) finds at least one declaration, *begin-expr* and *end-expr* are
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- `__range.begin()` and `__range.end()`, respectively;
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  - otherwise, *begin-expr* and *end-expr* are `begin(__range)` and
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- `end(__range)`, respectively, where `begin` and `end` are looked up in
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- the associated namespaces ([[basic.lookup.argdep]]). Ordinary
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- unqualified lookup ([[basic.lookup.unqual]]) is not performed.
 
 
 
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  ``` cpp
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  int array[5] = { 1, 2, 3, 4, 5 };
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  for (int& x : array)
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  x *= 2;
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  ```
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  In the *decl-specifier-seq* of a *for-range-declaration*, each
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  *decl-specifier* shall be either a *type-specifier* or `constexpr`. The
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  *decl-specifier-seq* shall not define a class or enumeration.
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  ### The range-based `for` statement <a id="stmt.ranged">[[stmt.ranged]]</a>
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+ The range-based `for` statement
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  ``` bnf
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+ 'for (' for-range-declaration ':' for-range-initializer ')' statement
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  ```
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+ is equivalent to
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+
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+ where
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+
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+ - if the *for-range-initializer* is an *expression*, it is regarded as
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+ if it were surrounded by parentheses (so that a comma operator cannot
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+ be reinterpreted as delimiting two *init-declarator*s);
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+ - `__range`, `__begin`, and `__end` are variables defined for exposition
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+ only; and
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+ - *begin-expr* and *end-expr* are determined as follows:
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+ - if the *for-range-initializer* is an expression of array type `R`,
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+ *begin-expr* and *end-expr* are `__range` and `__range + __bound`,
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+ respectively, where `__bound` is the array bound. If `R` is an array
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+ of unknown bound or an array of incomplete type, the program is
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+ ill-formed;
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+ - if the *for-range-initializer* is an expression of class type `C`,
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+ the *unqualified-id*s `begin` and `end` are looked up in the scope
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+ of `C` as if by class member access lookup (
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+ [[basic.lookup.classref]]), and if either (or both) finds at least
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+ one declaration, *begin-expr* and *end-expr* are `__range.begin()`
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+ and `__range.end()`, respectively;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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  - otherwise, *begin-expr* and *end-expr* are `begin(__range)` and
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+ `end(__range)`, respectively, where `begin` and `end` are looked up
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+ in the associated namespaces ([[basic.lookup.argdep]]).
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+ \[*Note 1*: Ordinary unqualified lookup ([[basic.lookup.unqual]])
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+ is not performed. — *end note*]
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+
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+ [*Example 1*:
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  ``` cpp
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  int array[5] = { 1, 2, 3, 4, 5 };
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  for (int& x : array)
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  x *= 2;
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  ```
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+ — *end example*]
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+
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  In the *decl-specifier-seq* of a *for-range-declaration*, each
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  *decl-specifier* shall be either a *type-specifier* or `constexpr`. The
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  *decl-specifier-seq* shall not define a class or enumeration.
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