You'll need to use an XML tool to compare two versions of a design element, a situation made more difficult due to the fact that the XML tool you use probably won't have any understanding of DXL, or the Notes database structure. While the Notes C++ API will give you access to all of the design elements and code streams used within a database, you'll need to learn new tools and a new programming language (C++) in order to go this route.

Fortunately, Delta makes it possible to compare all code changes from a single dialog box, without having to export any code, learn XML or DXL syntax , or learn any new programming languages. You can use Delta to quickly determine every instance where code has been changed, regardless of what language that code was written in (simple actions, formula, LotusScript, JavaScript, or Java), or where that code resides.

While the formula language is the most frequently used language in Notes databases, its syntax makes detailed comparisons of any kind difficult. The Notes formula language is macro based, where one @function may be nested within another @function, which is itself contained within another @function, all of which are invoked within one statement. Because of this, all Delta can tell you is when the formula code used in a design element doesn't match the formula code used in a later version of that design element. This is fortunately not the case with LotusScript.

Since LotusScript is a procedural language based on BASIC, each statement must reside on a separate line. This makes it possible for Delta to perform a line-by-line comparison of each LotusScript code stream. Delta uses different colors to represent lines of code that exist in the first database but not the second database (green), that exist in the second database but not the first database (blue), or that exist in both databases but are different (red). If you don't like the colors Delta uses to represent code differences, you can use the Preferences->Fonts menu to change them. This may be particularly necessary when you use Delta to create a report database of the differences, as the dark shades of green and blue used by default can be difficult to differentiate.

Delta also can perform line-by-line comparisons of JavaScript and Java code streams. While both languages allow you to include multiple statements on a single line (separated by a semi-colon), most programmers usually place each statement on a separate line as a best practice. You can cycle through the differences in the two code streams by clicking on the Prev Diff and Next Diff buttons shown in Figure B.

FIGURE B


Use the Prev Diff and Next Diff button to quickly cycle through code differences. Roll over picture for a larger image.

Product strengths
While Delta has many aspects that make it an excellent product, here are several that I feel are the most significant:

Delta is very easy to use. While reading through the help manual will help you use all of the product's features more effectively, you can start using Delta immediately after installing it.