Structure Constructors

A structure constructor lets you specify scalar values of a derived type. It takes the following form:

d-name (expr-list)

d-name

Is the name of the derived type.

expr-list

Is a list of expressions specifying component values. The values must agree in number and order with the components of the derived type. If necessary, values are converted (according to the rules of assignment), to agree with their corresponding components in type and kind parameters.

Description

A structure constructor must not appear before its derived type is defined.

If a component of the derived type is an array, the shape in the expression list must conform to the shape of the component array.

If a component of the derived type is a pointer, the value in the expression list must evaluate to an object that would be a valid target in a pointer assignment statement. (A constant is not a valid target in a pointer assignment statement.)

If all the values in a structure constructor are constant expressions, the constructor is a derived-type constant expression.

Examples

Consider the following derived-type definition:

TYPE EMPLOYEE

INTEGER ID

CHARACTER(LEN=40) NAME

END TYPE EMPLOYEE

This can be used to produce the following structure constructor:

EMPLOYEE(3472, "John Doe")

The following example shows a type with a component of derived type:

TYPE ITEM

REAL COST

CHARACTER(LEN=30) SUPPLIER

CHARACTER(LEN=20) ITEM_NAME

END TYPE ITEM

TYPE PRODUCE

REAL MARKUP

TYPE(ITEM) FRUIT

END TYPE PRODUCE

In this case, you must use an embedded structure constructor to specify the values of that component; for example:

PRODUCE(.70, ITEM (.25, "Daniels", "apple"))

See Also