iX Computer Systems - Edition 1 (32715-90001)

3- 31

10 I=1 10 I=1

20 PRINT (I LOR FNI(I)); I 20 PRINT (I OR FNI(I)); I

99 END 99 END

If array A has Maxindex elements, and Index is greater than Maxindex,

then the statement

100 IF (Index &> Maxindex) OR (A(Index) =5) THEN GOTO 500

does not evaluate A(Index), and an error does not occur. The statement

200 IF (Index &> Maxindex) LOR (A(Index) =5) THEN GOTO 600

does evaluate A(Index), and an error occurs (subscript out of range).

Table 3-26 is the truth table for the XOR operator. XOR is different

from the OR and LOR operators in that it returns TRUE only when the first

or the second operator is TRUE, but the operators are not both TRUE. The

OR and LOR operators return TRUE if one or both operands are TRUE.

Table 3-26. XOR Truth Table

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| X | Y | XORY |

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| TRUE | TRUE | FALSE |

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| TRUE | FALSE | TRUE |

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| FALSE | TRUE | TRUE |

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| FALSE | FALSE | FALSE |

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Examples These expressions are TRUE:

0 XOR 1 (3-(2+1)) XOR 85 (6 <=5) XOR (7+3)

1 XOR 0 35677 XOR (9-(3*3)) (X < (X-1) XOR ("A" = "A")

These expressions are FALSE:

0 XOR 0 ("cat" = "dog") XOR ("a" = "b") (X = (X+1)) XOR (X-X)

1 XOR 1 ("cat" < "dog") XOR ("a" < "b") 365 XOR 366

String Concatenation Operator

The string concatenation operator has two string operands and a string

result.