Informix Error -1393: The class class has already been defined.

Reasons / Common Causes

-1393 fires when a program attempts to define a class a second time — per the official guidance, this is a straightforward duplicate-definition condition.

1. A class defined twice in the same program, per the official guidance — the direct, only cause, often from the same module being included twice, or two modules both defining the same class name.

Solutions / Resolution

1. Locate both definitions of the class and remove the duplicate, keeping only one.
2. Check for a module accidentally included twice in the build, if the duplication isn't obvious from the source directly.

Examples

N/A

No specific triggering statement is documented — search the program (across all modules) for two definitions of the same class name.

Diagnostic Checks

1. Search the entire program (across all modules) for every definition of the class name, and confirm only one exists.
2. Check the build's module list for an accidental duplicate include.

Related Errors / Related Topics

• -1390 — "The class "class" has not been defined in any module in the program." The mirror-image restriction: a class used but never defined at all, rather than defined more than once.

A class was defined twice — remove the duplicate definition, or check for a doubly-included module.