6.219 VERIFY — Scan a string for the absence of a set of characters

Description:

Verifies that all the characters in a SET are present in a STRING.

If BACK is either absent or equals FALSE, this function returns the position of the leftmost character of STRING that is not in SET. If BACK equals TRUE, the rightmost position is returned. If all characters of SET are found in STRING, the result is zero.

Standard:

F95 and later

Class:

Elemental function

Syntax:

RESULT = VERIFY(STRING, SET[, BACK [, KIND]])

Arguments:

STRING	Shall be of type CHARACTER(*).
SET	Shall be of type CHARACTER(*).
BACK	(Optional) shall be of type LOGICAL.
KIND	(Optional) An INTEGER initialization expression indicating the kind parameter of the result.

Return value:

The return value is of type INTEGER and of kind KIND. If KIND is absent, the return value is of default integer kind.

Example:

          PROGRAM test_verify
            WRITE(*,*) VERIFY("FORTRAN", "AO")           ! 1, found 'F'
            WRITE(*,*) VERIFY("FORTRAN", "FOO")          ! 3, found 'R'
            WRITE(*,*) VERIFY("FORTRAN", "C++")          ! 1, found 'F'
            WRITE(*,*) VERIFY("FORTRAN", "C++", .TRUE.)  ! 7, found 'N'
            WRITE(*,*) VERIFY("FORTRAN", "FORTRAN")      ! 0' found none
          END PROGRAM
     

See also:

SCAN, INDEX intrinsic