Syntax error in Product Builder module

Recently we came across a small but annoying problem in the product builder modules.
Our product model, perfectly working for quite some time, refused to compile after a minor modification. The error message read:

Compilation error: *** Error: -1, Syntax error.

The error popped up when we compiled a code treenode from the product model. We checked our code, everything looked OK. We didn't make a typing error.

One of the product builder variables we used was named 'DDB'. No problem so far, but when we tried to use this variable in the code segment of our treenode, the error came up. Why?
When used in the code treenode, Ax will declare a variable in the class it creates for your product model, with the same name as used in the product model.
Only, DDB is a reserved name, as this is the name of a function in Ax (it calculates the accelerated depreciation of an asset). Variables in classes cannot be named after built-in functions.

So our solution: rename variable DDB to something else.
Problem solved, something learned.