STRUCTURE and RECORD - The GNU Fortran Compiler
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#### 6.2.1 `STRUCTURE` and `RECORD`

Record structures are a pre-Fortran-90 vendor extension to create user-defined aggregate data types. GNU Fortran does not support record structures, only Fortran 90's “derived types”, which have a different syntax.

In many cases, record structures can easily be converted to derived types. To convert, replace `STRUCTURE /`structure-name`/` by `TYPE` type-name. Additionally, replace `RECORD /`structure-name`/` by `TYPE(`type-name`)`. Finally, in the component access, replace the period (`.`) by the percent sign (`%`).

Here is an example of code using the non portable record structure syntax:

         ! Declaring a structure named ``item'' and containing three fields:
         ! an integer ID, an description string and a floating-point price.
         STRUCTURE /item/
           INTEGER id
           CHARACTER(LEN=200) description
           REAL price
         END STRUCTURE

         ! Define two variables, an single record of type ``item''
         ! named ``pear'', and an array of items named ``store_catalog''
         RECORD /item/ pear, store_catalog(100)

         ! We can directly access the fields of both variables
         pear.id = 92316
         pear.description = "juicy D'Anjou pear"
         pear.price = 0.15
         store_catalog(7).id = 7831
         store_catalog(7).description = "milk bottle"
         store_catalog(7).price = 1.2

         ! We can also manipulate the whole structure
         store_catalog(12) = pear
         print *, store_catalog(12)

This code can easily be rewritten in the Fortran 90 syntax as following:

         ! ``STRUCTURE /name/ ... END STRUCTURE'' becomes
         ! ``TYPE name ... END TYPE''
         TYPE item
           INTEGER id
           CHARACTER(LEN=200) description
           REAL price
         END TYPE

         ! ``RECORD /name/ variable'' becomes ``TYPE(name) variable''
         TYPE(item) pear, store_catalog(100)

         ! Instead of using a dot (.) to access fields of a record, the
         ! standard syntax uses a percent sign (%)
         pear%id = 92316
         pear%description = "juicy D'Anjou pear"
         pear%price = 0.15
         store_catalog(7)%id = 7831
         store_catalog(7)%description = "milk bottle"
         store_catalog(7)%price = 1.2

         ! Assignments of a whole variable do not change
         store_catalog(12) = pear
         print *, store_catalog(12)