INTEGER
Purpose
An INTEGER type declaration statement specifies the length and attributes of objects and functions of type integer. Initial values can be assigned to objects.
Syntax
where:
- attr_spec
- is any of the following:
- kind_selector
-
- specifies the length of integer entities: 1, 2, 4 or 8. int_literal_constant cannot
specify a kind type parameter.
- attr_spec
- For detailed information on rules about a particular attribute, refer to the statement of the same name.
- intent_spec
- is either IN, OUT, or INOUT
- ::
- is the double colon separator. Use the double colon separator when you specify attributes, =constant_expr, or => NULL().
- array_spec
- is a list of dimension bounds
- entity_decl
-
>>-a--+-+------------------+--+------------------+-+------------>
| | (1) (2) | '-(--array_spec--)-' |
| '- * ------len-----' |
| (3) (4) |
'-(--array_spec--)-- * ------len-------------'
>--+----------------------------------+------------------------><
| (5) |
'-+-/--initial_value_list--/-----+-'
+- = --constant_expr-----------+
'- => --NULL()-----------------'
Notes:- IBM extension.
- IBM extension.
- IBM extension.
- IBM extension.
- IBM extension.
-
- a
- is an object name or function name. array_spec cannot be specified for a function name with an implicit interface.
- len
- overrides the length as specified in kind_selector,
and cannot specify a kind type parameter. The entity length must be
an integer literal constant that represents one of the permissible
length specifications.
- initial_value
- provides an initial value for the entity specified by the immediately
preceding name
- constant_expr
- provides a constant expression for the entity specified by the immediately preceding name
- => NULL()
- provides the initial value for the pointer object
Rules
- If => appears in a component initialization, the POINTER attribute must appear in the attr_spec_list.
- If = appears in a component initialization, the POINTER attribute cannot appear in the component attr_spec_list.
- The compiler will evaluate constant_expr within the scoping unit of the type definition.
If => appears for a variable, the object must have the POINTER attribute.
If constant_expr appears for a variable, the object cannot have the POINTER attribute.
Entities in type declaration statements are constrained by the rules of any attributes specified for the entities, as detailed in the corresponding attribute statements.
The type declaration statement overrides the implicit type rules in effect. You can use a type declaration statement that confirms the type of an intrinsic function. The appearance of a generic or specific intrinsic function name in a type declaration statement does not cause the name to lose its intrinsic property.
An
object cannot be initialized in a type declaration statement if it
is a dummy argument, an allocatable object, a pointer, a function
result, an object in blank common, an integer pointer, an external
name, an intrinsic name, or an automatic object. Nor can an object
be initialized if it has the AUTOMATIC attribute.
The object may be initialized if it appears in a named common block
in a block data program unit or if it
appears in a named common block in a module or submodule.
You can initialize pointers using => NULL().
The specification expression of an array_spec can be a nonconstant expression if the specification expression appears in an interface body or in the specification part of a subprogram. Any object being declared that uses this nonconstant expression and is not a dummy argument or a pointee is called an automatic object.
An attribute cannot be repeated in a given type declaration statement, nor can an entity be explicitly given the same attribute more than once in a scoping unit.
constant_expr must be specified if the statement contains the PARAMETER attribute. If the entity you are declaring is a variable, and constant_expr or NULL() is specified, the variable is initially defined.
If the entity you are declaring is a derived type component, and constant_expr or NULL() is specified, the derived type has default initialization.
a becomes defined with the value determined by constant_expr, in accordance with the rules for intrinsic assignment. If the entity is an array, its shape must be specified either in the type declaration statement or in a previous specification statement in the same scoping unit. A variable or variable subobject cannot be initialized more than once. If a is a variable, the presence of constant_expr or NULL() implies that a is a saved object, except for an object in a named common block. The initialization of an object could affect the fundamental storage class of an object.
An array_spec specified in the entity_decl takes precedence over the array_spec in the DIMENSION attribute.
An array
function result that does not have the 
ALLOCATABLE or 
POINTER attribute
must have an explicit-shape array specification.
If the entity declared is a function, it must not have an accessible explicit interface unless it is an intrinsic function.
If T or F,
defined previously as the name of a constant, appears in a type declaration
statement, it is no longer an abbreviated logical constant but the
name of the named constant.
Examples
MODULE INT
INTEGER, DIMENSION(3) :: A,B,C
INTEGER :: X=234,Y=678
END MODULE INTRelated information
- Integer
- Constant expressions
- Determining Type, for details on the implicit typing rules
- Array declarators
- Automatic objects
- Storage classes for variables (IBM extension)
- DATA, for details on initial values
