Informix Error -4092: Type mismatch between CLASS and non-CLASS type.

Cause and resolution

Type mismatch between CLASS and non-CLASS type.

The compiler attempted to convert the result of one expression to conform with the type of another expression, and only one of them was a CLASS. Either both must be CLASS type, or neither can be.

Oninit® Troubleshooting Guidance

Reasons / Common Causes

-4092 fires when the compiler tries to reconcile two expressions' types and only one of them is a CLASS — per the official guidance, either both expressions must be CLASS type, or neither can be.

An expression pairing a class-typed value with a non-class type, per the official guidance — the direct, only cause.

Solutions / Resolution

Make both sides of the expression consistently class-typed or non-class-typed.

Examples

Comparing a class instance to a plain value

DEFINE o Order
IF o = 5 THEN
  -- -4092: o is a CLASS, 5 is not
END IF

Corrected

IF o.order_id = 5 THEN
  ...
END IF

Diagnostic Checks

Check every expression pairing a class-typed value with another type, and make both sides consistent.

Related Errors / Related Topics

-4091 — "Cannot assign to or refer to an array as a whole. Use indexing to refer to individual elements." The same type-reconciliation principle applied to ARRAY values rather than CLASS values.
-4093 — "Type mismatch between RECORD and non-RECORD type." The same type-reconciliation principle applied to RECORD values rather than CLASS values.

An expression pairs a CLASS-typed value with a non-class type — make both sides consistent.