tests/cases/compiler/implementClausePrecedingExtends.ts(2,22): error TS1173: 'extends' clause must precede 'implements' clause. ==== tests/cases/compiler/implementClausePrecedingExtends.ts (1 errors) ==== class C { foo: number } class D implements C extends C { } ~~~~~~~ !!! error TS1173: 'extends' clause must precede 'implements' clause.