file1.ts(1,15): error TS2300: Duplicate identifier 'C1'.
file1.ts(3,15): error TS2300: Duplicate identifier 'C1'.
file1.ts(5,15): error TS2300: Duplicate identifier 'C2'.
file1.ts(7,11): error TS2300: Duplicate identifier 'C2'.
file1.ts(9,15): error TS2300: Duplicate identifier 'C2'.
file2.ts(1,15): error TS2300: Duplicate identifier 'C3'.
file3.ts(1,15): error TS2300: Duplicate identifier 'C3'.


==== file1.ts (5 errors) ====
    declare class C1 {}
                  ~~
!!! error TS2300: Duplicate identifier 'C1'.
    
    declare class C1 {}
                  ~~
!!! error TS2300: Duplicate identifier 'C1'.
    
    declare class C2 {}
                  ~~
!!! error TS2300: Duplicate identifier 'C2'.
    
    interface C2 {}
              ~~
!!! error TS2300: Duplicate identifier 'C2'.
    
    declare class C2 {}
                  ~~
!!! error TS2300: Duplicate identifier 'C2'.
    
==== file2.ts (1 errors) ====
    declare class C3 { }
                  ~~
!!! error TS2300: Duplicate identifier 'C3'.
!!! related TS6203 file3.ts:1:15: 'C3' was also declared here.
    
==== file3.ts (1 errors) ====
    declare class C3 { }
                  ~~
!!! error TS2300: Duplicate identifier 'C3'.
!!! related TS6203 file2.ts:1:15: 'C3' was also declared here.