$ChkPat

The $ChkPat function verifies the syntax of a pattern. If the pattern is valid, a null string is returned; otherwise, an error message string is returned.

Syntax

$ChkPat(pattern[,language])

Where:

• The required pattern argument is the string of characters to verify, which can be a literal enclosed in quotation marks or a %variable.

  See the description of SOUL patterns.

• The optional language argument specifies the language to use. The language argument is handled as follows:
  • If language is omitted, 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 the name of a valid language enclosed in quotation marks or a %variable containing a valid language. If the value you enter is not supported, the request is canceled with an error message. See the LANGUSER parameter for the valid values.

Without $ChkPat, pattern syntax errors can cause cancellation of the request or require the coding of complex ON units.

Examples

For U.S. English:

%PAT='ABC*' %X=$chkpat(%PAT) IF %X NE '' THEN PRINT %X JUMP TO ERROR.RETURN END IF

For French Canadian:

%PAT='pêché' %X=$chkpat(%PAT,'FRENCHC') IF %X NE '' THEN PRINT %X JUMP TO ERROR.RETURN END IF

Usage notes

$ChkPat supports language-sensitive specification of patterns through an optional second parameter (such as $Alpha and $AlphNum).

All characters X'00' through X'FF' are valid in a pattern presented to the SOUL pattern matcher. The $ChkPat function no longer invokes either of the following messages when it encounters these characters.

M204.1688: errortype IN PATTERN 'pattern' AT CHARACTER char M204.1689: errortype IN PATTERN 'pattern' AT CHARACTER char