Constants and Expressions
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Constants
The Recital/4GL supports the following constants:
| Datatype | Description |
|---|---|
| Character | A string of ASCII characters up to 65535 characters in length. Delimited by double quotes "", single quotes ‘’ or square brackets [] |
| Numeric | An integer number of up to 16 digits (0-9) or a floating point number of up to 25 digits (9 are reserved for decimal places) and one decimal point. |
| Date | A combination of digits and separators delimited by curly braces {}. The format is determined by the SET DATE and SET CENTURY commands. |
| Logical | A choice of two values, .T. for true, .F. for false (true and false can also be used themselves) |
Hexadecimal numbers
Hexadecimal numbers, prefixed by 0x, can be used in place of decimal numbers except in the data entry/modification of numerics. (Linux platforms only).
? BITAND(0x67452301,0xFFFFFFFF)
Results of expressions will still be returned as decimal numbers.
? 0x1a * 2 52
The TRANSFORM() function can be used to return a numeric as a hexadecimal.
? transform((0x1a * 2),"@0") 0x00000034
Expressions
The TYPE() function can be used to determine the data type of any expression.
| uMemvar | TYPE("uMemvar") | Type |
|---|---|---|
| [hello] | ’C’ | Character |
| ’goodbye’ | ’C’ | Character |
| "RECITAL" | ’C’ | Character |
| 1234 | ’N’ | Numeric |
| 1234.56 | ’N’ | Numeric |
| "1234.56" | ’C’ | Character |
| 0x2b | ’N’ | Numeric |
| {01/01/96} | ’D’ | Date |
| {01/01/1996} | ’D’ | Date |
| "01/01/96" | ’C’ | Character |
| .T. | ’L’ | Logical |
| .F. | ’L’ | Logical |
| opentags | ’P’ | Procedure |
| OMyObj | ’O’ | Object |
| Undetermined Type | ’U’ | Undefined |
