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─────Logical Expressions────────────────────────────────────────────────────
 
     Logical expressions produce logical values. Basic operands used in
     logical expressions are:
 
          ■ Logical constants or variables
 
          ■ Logical array-elements
 
          ■ Logical function references
 
          ■ Relational expressions
 
          ■ Integer constants or variables
 
     Logical expressions are constructed from the basic operands and
     logical operators.
 
     Operator     Operation              Precedence
 
     .NOT.        Negation               1 (highest)
 
     .AND.        Conjunction            2
 
     .OR.         Inclusive disjunction  3
 
     .XOR.        Exclusive disjunction  4
 
     .EQV.        Equivalence            4
 
     .NEQV.       Nonequivalence         4
 
     All of these are binary operators except .NOT., which is unary
     and precedes its operand.
 
     Logical operators allow only arguments of the LOGICAL type.
     Microsoft FORTRAN also permits integer arguments, which may be
     integer constants, integer variables, integer structure elements,
     or integer expressions. Operations are "bitwise." For example,
     the expression "k .XOR. m" performs an "exclusive-or" comparison
     on matching bits in the operands, and sets or clears the
     corresponding bit in the integer value it returns. If both
     operands are not of the same integer type, the lower-precision
     operand is converted to the higher-precision type.
 
     The result of comparing two integer expressions with a logical
     operator is of INTEGER type, not LOGICAL.
 
     When two consecutive operations are of equal precedence, the
     leftmost operation is performed first.
                                    -♦-