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emptyObjectTypes

Reports empty object type literals and empty interfaces that are often used incorrectly.

✅ This rule is included in the ts logical and logicalStrict presets.

The {} (“empty object”) type in TypeScript is a common source of confusion. It actually represents any non-nullish value, not an empty object. This includes primitives like strings and numbers.

Similarly, an empty interface interface Foo {} is equivalent to {}.

If you want to represent any object, use object. If you want any value, use unknown.

Examples

Section titled “Examples”
AEty53 EmptA53 {<};d ivclassNa="meco"><};d>AEinterfa53 Empty <{}d ivclassNa="meco"><{}d>AEle53val7<2:sp ansty="le--0:#C792EA;--1:#8844">AE <{}sp ansty="le--0:#D6DEEB;--1:#403F">5<3;d ivclassNa="meco"><};d>AEfuncti5<3 sp ansty="le--0:#82AAFF;--1:#3B61">B0f1<1(sp ansty="le--0:#D7DBE0;--1:#403F">53par7<2:sp ansty="le--0:#D6DEEB;--1:#403F">53 <{}sp ansty="le--0:#D9F5DD;--1:#1111">1<1)sp ansty="le--0:#D6DEEB;--1:#403F">53 <{}d ivclassNa="meco"><{}d>
44AE3F53 HasMemb4<4AE= spans="tyle--0:#D6DEEB;--1:#40">3F53 {< foo spans="tyle--0:#7FDBCA;--1:#09">6361B0st3F5<3 } ;divclass="Name"><;di vdivclass="Nameexpressive-">44AEinter3F53 HasMembe3F<53 spans="tyle--0:#D6DEEB;--1:#40">3F5<3foo spans="tyle--0:#7FDBCA;--1:#09">6361B0st33<}di vdivclass="Nameexpressive-">44AE3F53v64<4AE spans="tyle--0:#C5E478;--1:#3B">61B0ob3<;di vdivclass="Nameexpressive-">44AE3F53v64<4AE spans="tyle--0:#C5E478;--1:#3B">61B0unk3<;di vdivclass="Nameexpressive-">6376// Empty object in intersection types is allowed (useful for NonNulla44AE3F53 NonNulla1<111T spans="tyle--0:#D6DEEB;--1:#40">3F<53> spans="tyle--0:#C792EA;--1:#88">4 ><4AE= spans="tyle--0:#D6DEEB;--1:#40">31<111T spans="tyle--0:#D6DEEB;--1:#40">363F53< {} ;divclass="Name">< {}><;di vdivclass="Nameexpressive-">6376// Empty interface extending multiple interfaces is all44AEinter3F53 Combi44AEext361B<0Foo spans="tyle--0:#D6DEEB;--1:#40">3F<53, spans="tyle--0:#C5E478;--1:#3B">61B<0Bar spans="tyle--0:#D6DEEB;--1:#40">3F5<3 { }divclass="Name">

Options

Section titled “Options”

This rule is not configurable.

When Not To Use It

Section titled “When Not To Use It”

If your code commonly needs to represent the “any non-nullish value” type, this rule may not be for you. Projects that extensively use type operations such as conditional types and mapped types may benefit from disabling this rule.

Further Reading

Section titled “Further Reading”

Equivalents in Other Linters

Section titled “Equivalents in Other Linters”