New R/BASIC Operators
| Published By | Date | Version | Knowledge Level | Keywords |
|---|---|---|---|---|
| Revelation Technologies | 02 JUN 1992 | 2.1X | INTERMEDIATE | R/BASIC, RBASIC, OPERATORS, CASESENSITIVE, CASE, SENSITIVE |
Advanced Revelation 2.1 introduces six new R/BASIC comparison operators. These operators are intended to be used in situations where a case insensitive comparison is desired.
The operators and their meanings are given in the following table:
| Operator | Meaning |
|---|---|
| _EQC | Equal |
| _NEC | Not Equal |
| _LTC | Less Than |
| _GTC | Greater Than |
| _LEC | Less Than or Equal |
| _GEC | Greater Than or Equal |
To maintain compatibility with existing programs, the new operators are prefixed with a "_" (underscore). This prevents the compiler from confusing the operator with, for example, a variable called NEC.
The "C" suffix is a reminder that the comparison will be case insensitive.
Using the New Operators
Prior to Advanced Revelation 2.1 you would perform a case-insensitive comparison using code similar to that in Figure 1. Both strings are converted to the same case and then the comparison is done.
Figure 2 demonstrates how the same program is written using one of the new operators.
Note: For information on how comparisons are evaluated, see the section "Comparisons in R/LIST" in the "Changes to R/LIST" chapter of the Advanced Revelation 2.1 Addendum. The discussion applies to both R/LIST and R/BASIC.
Examples
Figure 1
DECLARE SUBROUTINE MSG
VAR1 = "Revelation"
VAR2 = "ReVelATION"
CONVERT @LOWER.CASE TO @UPPER.CASE IN VAR1
CONVERT @LOWER.CASE TO @UPPER.CASE IN VAR2
IF VAR1 = VAR2 THEN
MSG("Match", "", "", "")
END ELSE
MSG("No Match", "", "", "")
END
Figure 2
DECLARE SUBROUTINE MSG
VAR1 = "Revelation"
VAR2 = "ReVelATION"
IF VAR1 _EQC VAR2 THEN
MSG("Match", "", "", "")
END ELSE
MSG("No Match", "", "", "")
END