Last week, we explored editing SGML properties with Legato. By using some of the Legato SDK functions, we can read the properties of an SGML tag and change those properties to new values. This is pretty simple and straightforward. However, what if we want to do something based on a particular setting? For example, what if we want to employ an “Indent Body of Paragraph” function, where the first line of the paragraph doesn’t move but the subsequent lines are indented? We can’t simply read the indent value and add to it because we cannot guarantee that the same unit of measurement is being used. We need to read the unit, normalize it into a standard unit, add to it, convert it back to the original measurement style, and write it back out. It’s a bit more involved than simply setting properties, but it lets us perform some pretty interesting operations.