Re: regexec() trouble -- MIDRANGE-L


[SNIP]

// From: http://www.regular-expressions.info/email.html
RegPattern = '^[A-Z0-9._%-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$';
rc = regcomp(reg: %trimr(RegPattern): REG_BASIC+REG_ICASE+REG_NOSUB);
// Why won't this work?!?
Chr256 = 'test@xxxxxxxxxxx';
rc = regexec(reg: %trim(Chr256): 0: match: 0);

[SNIP]

The problem is the plus symbol. On the iSeries (I don't know aboutelsewhere?) the + symbol is only supported in extended regularexpressions, it's not supported in basic ones.

What the + symbol does is match "one or more" of the preceding character.This is in contrast to the * (asterisk) symbol which matches "zero ormore" of the preceding symbol.

So if you had a pattern of [A-Z]+ (in an environment that supports theplus symbol) it'll match one or more of the letters from A-Z. Or, slightlymore complicated (in your example) you have [A-Z0-9._%-]+, which willmatch one or more of any letter, any number, a dot, a percent symbol, or adash.

If you change it to [A-Z0-9._%-]* it'll match zero or more -- which meansthat it could omit those characters entirely. Whereas with a +, there hasto be at least one.

Since the iSeries doesn't support the + operator, you could achieve thesame results by changing your pattern to look like this:


^[A-Z0-9._%-][A-Z0-9._%-]*@[A-Z0-9.-][A-Z0-9.-]*\.[A-Z]{2,4}$

All I did was repeat the bracketed expressions, and change the + to a *.Now it has to match one character. Followed by zero or more characters.That'd have the same effect as the original expression you posted, andwould work on the iSeries as a basic expression.

The other alternative is to compile your expression as an EXTENDED regularexpression instead of a BASIC one. Extended expressions DO support theplus symbol, and therefore your original expression should work fine. Tomake it extended, change REG_BASIC to REG_EXTENDED on the call toregcomp().

I hope my explanation makes sense, I was struggling to find the rightwords!


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Scott Klement  http://www.scottklement.com