tests/cases/conformance/types/members/duplicateStringIndexers.ts(6,9): error TS2374: Duplicate string index signature. tests/cases/conformance/types/members/duplicateStringIndexers.ts(11,9): error TS2374: Duplicate string index signature. tests/cases/conformance/types/members/duplicateStringIndexers.ts(16,9): error TS2374: Duplicate string index signature. tests/cases/conformance/types/members/duplicateStringIndexers.ts(21,9): error TS2374: Duplicate string index signature. tests/cases/conformance/types/members/duplicateStringIndexers.ts(26,9): error TS2374: Duplicate string index signature. tests/cases/conformance/types/members/duplicateStringIndexers.ts(31,9): error TS2374: Duplicate string index signature. ==== tests/cases/conformance/types/members/duplicateStringIndexers.ts (6 errors) ==== // it is an error to have duplicate index signatures of the same kind in a type module test { interface Number { [x: string]: string; [x: string]: string; ~~~~~~~~~~~~~~~~~~~~ !!! error TS2374: Duplicate string index signature. } interface String { [x: string]: string; [x: string]: string; ~~~~~~~~~~~~~~~~~~~~ !!! error TS2374: Duplicate string index signature. } interface Array { [x: string]: T; [x: string]: T; ~~~~~~~~~~~~~~~ !!! error TS2374: Duplicate string index signature. } class C { [x: string]: string; [x: string]: string; ~~~~~~~~~~~~~~~~~~~~ !!! error TS2374: Duplicate string index signature. } interface I { [x: string]: string; [x: string]: string; ~~~~~~~~~~~~~~~~~~~~ !!! error TS2374: Duplicate string index signature. } var a: { [x: string]: string; [x: string]: string; ~~~~~~~~~~~~~~~~~~~~ !!! error TS2374: Duplicate string index signature. } }