2.1.4  Array Shaping

If an expression has a type of pointer to T, then a shape-operator can be used to specify the extent of that pointer. In other words, the shape-operator is used to reinterpret, as an n-dimensional array, the region of memory to which that expression points.

Formally, the syntax of the shape-operator is as follows:  

 
 shaped-expression  := ([s1][s2]...[sn])cast-expression
       

The result of applying the shape-operator to an expression is an lvalue expression with an n-dimensional array type with dimensions s₁ ×s₂ …×s_n and element type T.

The precedence of the shape-operator is the same as a type cast.

Each s_i is an integral type expression that must evaluate to a positive integer.

RestrictionsRestrictions to the shape-operator are as follows:

• The type T must be a complete type.
• The shape-operator can appear only in clauses where it is explicitly allowed.
• The result of a shape-operator must be a named array of a list item.
• The type of the expression upon which a shape-operator is applied must be a pointer type.
  ∙ If the type T is a reference to a type T’, then the type will be considered to be T’ for all purposes of the designated array.