13af6ab5fSopenharmony_ci# ``delete`` operator is not supported 23af6ab5fSopenharmony_ci 33af6ab5fSopenharmony_ciRule ``arkts-no-delete`` 43af6ab5fSopenharmony_ci 53af6ab5fSopenharmony_ci**Severity: error** 63af6ab5fSopenharmony_ci 73af6ab5fSopenharmony_ciArkTS assumes that object layout is known at compile time and cannot be 83af6ab5fSopenharmony_cichanged at runtime. Thus the operation of deleting a property makes no sense. 93af6ab5fSopenharmony_ci 103af6ab5fSopenharmony_ci 113af6ab5fSopenharmony_ci## TypeScript 123af6ab5fSopenharmony_ci 133af6ab5fSopenharmony_ci 143af6ab5fSopenharmony_ci``` 153af6ab5fSopenharmony_ci 163af6ab5fSopenharmony_ci class Point { 173af6ab5fSopenharmony_ci x?: number = 0.0 183af6ab5fSopenharmony_ci y?: number = 0.0 193af6ab5fSopenharmony_ci } 203af6ab5fSopenharmony_ci 213af6ab5fSopenharmony_ci let p = new Point() 223af6ab5fSopenharmony_ci delete p.y 233af6ab5fSopenharmony_ci 243af6ab5fSopenharmony_ci``` 253af6ab5fSopenharmony_ci 263af6ab5fSopenharmony_ci## ArkTS 273af6ab5fSopenharmony_ci 283af6ab5fSopenharmony_ci 293af6ab5fSopenharmony_ci``` 303af6ab5fSopenharmony_ci 313af6ab5fSopenharmony_ci // To mimic the original semantics, you may declare a nullable type 323af6ab5fSopenharmony_ci // and assign null to mark value absence: 333af6ab5fSopenharmony_ci 343af6ab5fSopenharmony_ci class Point { 353af6ab5fSopenharmony_ci x: number | null = 0 363af6ab5fSopenharmony_ci y: number | null = 0 373af6ab5fSopenharmony_ci } 383af6ab5fSopenharmony_ci 393af6ab5fSopenharmony_ci let p = new Point() 403af6ab5fSopenharmony_ci p.y = null 413af6ab5fSopenharmony_ci 423af6ab5fSopenharmony_ci``` 433af6ab5fSopenharmony_ci 443af6ab5fSopenharmony_ci## See also 453af6ab5fSopenharmony_ci 463af6ab5fSopenharmony_ci- Recipe 001: Objects with property names that are not identifiers are not supported (``arkts-identifiers-as-prop-names``) 473af6ab5fSopenharmony_ci- Recipe 002: ``Symbol()`` API is not supported (``arkts-no-symbol``) 483af6ab5fSopenharmony_ci- Recipe 029: Indexed access is not supported for fields (``arkts-no-props-by-index``) 493af6ab5fSopenharmony_ci- Recipe 060: ``typeof`` operator is allowed only in expression contexts (``arkts-no-type-query``) 503af6ab5fSopenharmony_ci- Recipe 066: ``in`` operator is not supported (``arkts-no-in``) 513af6ab5fSopenharmony_ci 523af6ab5fSopenharmony_ci 53