Using VPLUS: An Introduction to Forms Design (32209-90004)
4-11
Expressions. Expressions can be formed only with
numeric
data types,
and
can only use the operators shown in Table 4-3.
Table 4-3. Operators
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| | |
| + | addition |
| - | subtraction |
| % | percent |
| * | multiplication |
| / | division |
| | |
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The Pattern Parameter
The MATCH statement pattern allows you to group characters and to repeat
single or grouped characters. Grouping is indicated by pairs of brack-
ets
or braces; repetition by following the character or grouped characters
by
a plus (+) or asterisk (*) character. The pattern control characters are
shown in Table 4-4. The choice of symbols depends on whether a character
or group of characters can be omitted or not. However, leading and
trailing blanks are not allowed in a MATCH pattern.
You can also specify that the pattern include a specific character such
as the hyphen shown in the example above. If you want to include any of
the pattern control characters as a specific character, you must precede
it by an exclamation point (!). For example:
MATCH !a???c Value must start with the letter a followed by any three
characters, and then the letter c.
MATCH a???c Value must start with any upper or lowercase letter
followed by any three characters and then the letter
lowercase c.
Table 4-4. Pattern Control Characters
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| | |
| Character | Meaning |
| | |
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| | |
| a | upper or lowercase letter of alphabet (A-Z,a-z) |
| | |
| u | uppercase letter of alphabet (A-Z) |
| | |
| l | lowercase letter of alphabet (a-z) |
| | |
| b | blank (must not be specified as first or last character of pattern) |
| | |
| d | any digit (0-9) |
| | |
| ? | any character |
| | |
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