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drlippman / IMathAS

IMathAS Online Math Assessment
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Allow for superscript charges #333

Closed bibbca closed 2 years ago

bibbca commented 2 years ago

Adds regex to allow for superscript charges in HTML display chemistry library macro of the form digit+, digit-, +, or -.

drlippman commented 2 years ago

Please be sure to test all cases. Your regex doesn't quite work here, since you have two paren capture groups, so the (\+|\-) group would be $2, and doesn't result in the desired output.

I think you can fix it by changing the regex so it has just one capture group that contains the 4 possibilities: $c = preg_replace('/\^(\d\+|\d\-|\+|\-)/','<sup>$1</sup>',$c);

Is it possible the charges could ever be two-digit? If so, then you'd want: $c = preg_replace('/\^(\d+\+|\d+\-|\+|\-)/','<sup>$1</sup>',$c);

bibbca commented 2 years ago

Thanks so much! I'm really new to regex. This is very helpful