Avoid unsafe declaration merging

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Metadata

ID: typescript-best-practices/no-unsafe-declaration-merging

Language: TypeScript

Severity: Error

Category: Error Prone

Description

Do not merge class and interface declarations. The compiler won’t check property initialization, which might lead to runtime errors.

Non-Compliant Code Examples

interface Foo {}
class Foo {}

Compliant Code Examples

interface Foo {}
class Bar implements Foo {}

namespace Baz {}
namespace Baz {}
enum Baz {}

namespace Qux {}
function Qux() {}

How to use this rule

1
2
rulesets:
  - typescript-best-practices     # Rules to enforce TypeScript best practices.

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