$Alpha
The $Alpha function verifies whether a string is composed only of characters which are valid in the specified (or default) language.
- 1 is returned for a true condition.
- 0 is returned for a false condition if:
- the string contains digits, spaces, or punctuation marks, or
- the string is null, or
- U.S. English characters in the string have accent marks.
Syntax
The format of the $Alpha function is:
$Alpha(string [,language])
Where:
- string represents the string to be verified. The string must be one of the following:
- A literal enclosed in quotation marks
- A %variable
- A field name without quotation marks. In this case, the function call must be embedded in a FOR EACH RECORD loop where the current value of the field is verified.
- The optional language argument specifies the language to use. The language argument is handled as follows:
- You can enter a literal enclosed in quotation marks or a %variable containing a valid language name. If the value you enter is not a supported language, the request is canceled with the following error message. See the LANGUSER parameter for the valid values.
M204.2340: INVALID LANGUAGE ARGUMENT: 'language' FOR $FUNCTION: ALPHA
- If you omit the language argument, Model 204 performs the validation in U.S. English, even if the value of the LANGUSER parameter is not
US
, and lowercase characters are not recognized. - An asterisk enclosed in quotation marks ('*') instructs Model 204 to use the value of the LANGUSER parameter.
- You can enter a literal enclosed in quotation marks or a %variable containing a valid language name. If the value you enter is not a supported language, the request is canceled with the following error message. See the LANGUSER parameter for the valid values.
Examples
The following table has examples of the string and language arguments as literals.
Function code... | Returns... |
---|---|
$alpha('JOHN','US') |
1 |
$alpha('MÂCON','FRENCHC') |
1 |
$alpha('MÂCON','US') |
0 |
$alpha('JOHN SMITH','US') |
0 |
$alpha('ÎLE D'ORLÉANS','FRENCHC') |
0 |
$alpha('12A','US') |
0 |
$alpha('12A','FRENCHC') |
0 |
In the following code example, the request sorts and prints the names of agents whose name contains nonalphabetic characters. The quoted asterisk in the $Alpha call causes Model 204 to verify the contents of the field AGENT
against whatever language is indicated by the value of the LANGUSER parameter:
RESET LANGUSER 'FRENCHC' BEGIN POL.HOLDERS: FIND ALL RECORDS FOR WHICH RECTYPE = POLICYHOLDER END FIND FOR EACH RECORD IN POL.HOLDERS IF NOT $alpha (AGENT, '*') THEN PLACE RECORD ON LIST BADNAME END IF END FOR ORDERED.LIST: SORT RECORDS ON LIST BADNAME BY AGENT FOR EACH RECORD IN ORDERED.LIST PRINT AGENT END FOR END
Note: For upward compatibility reasons, $Alpha and $Alphnum do not recognize lowercase English letters as alphabetic characters unless a non-null language parameter is specified.