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─────CASE───────────────────────────────────────────────────────────────────
 
     Action
 
     Marks the beginning of a statement block that executes if an item
     in its expression list matches the test expression in a SELECT CASE
     statement.
 
     Syntax
 
     CASE {DEFAULT | (expressionlist)}
          statementblock
 
     Parameter          Description
 
     DEFAULT            The keyword indicating that the following
                        statement block is to execute if none of the
                        expressions in any other CASE statements match
                        the test expression constants or ranges of
                        constants.
 
     expressionlist     A list of constants or ranges of constants.
                        The values must be of type INTEGER, LOGICAL,
                        or CHARACTER*1. If the test expression matches
                        one of the values, the following block of
                        statements executes.
 
     statementblock     Executable statements (may be empty).
 
     Remarks
 
     The CASE statement may only appear within the SELECT CASE...END
     SELECT construct.
 
     Indicate ranges by placing a colon (:) between two values (such as
     5:10 or 'A':'Z').
 
        ■ Omitting the low end of a range (:10 or :'Z') causes the CASE
          statement block to execute for any test expression with a
          value less than or equal to the specified upper bound.
 
        ■ Omitting the high end of the range executes the statement
          block for any test expression with a value greater than or
          equal to the low end given (such as 5: or 'a':).
 
     The CASE DEFAULT statement is optional. You can include only one
     CASE DEFAULT statement in a SELECT CASE block.
 
     See Also:  ◄SELECT CASE...END SELECT►
 
     Example
 
           CHARACTER*1  cmdchar
 
           SELECT CASE (cmdchar)
           CASE ('0')
              WRITE (*, *) "Must retrieve one to nine files"
           CASE ('1':'9')
              CALL RetrieveNumFiles (cmdchar)
           CASE ('A', 'd')
              CALL AddEntry
           CASE ('D', 'd')
              CALL DeleteEntry
           CASE ('H', 'h')
              CALL Help
           CASE ('R':'T', 'r':'t')
              WRITE (*, *) "REDUCE, SPREAD and TRANSFER commands ",
          +                          "not yet supported"
           CASE DEFAULT
              WRITE (*, *) "Command not recognized; please re-enter"
           END SELECT
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