Non-standard
This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
Obsolete since Gecko 2 (Firefox 4 / Thunderbird 3.3 / SeaMonkey 2.1)
This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.
A propriedade __count__ usada para armazenar a contagem de propriedades enumeráveis sobre o objeto, mas ele foi removido.
Sintaxe
obj.__count__
Exemplos
{ 1: 1 }.__count__ // 1
[].__count__ // 0
[1].__count__ // 1
[1, /* hole */, 2, 3].__count__ // 3
Especificações
Não faz parte de qualquer especificação.
Compatibilidade de navegadores
No compatibility data found. Please contribute data for "javascript.builtins.Object.count" (depth: 1) to the MDN compatibility data repository.