流量类型错误：未知类型的属性。此类型与阵列类型不兼容

Question

我有以下JSX。例如：

{ 
    event.divisions && 
    event.divisions.edges && 
    (event.divisions.edges: Array<Object>) 
    .map(d => d.node) 
    .map(division => (
     <div>{division}</div> 
    )) 
} 

没有投射它告诉我它缺少一个注释。随着铸造，我得到以下错误：

81: (event.divisions.edges: Array<Object>) 
     ^^^^^^^^^^^^^^^^^^^^^ property `edges` of unknown type. This type is incompatible with 
81: (event.divisions.edges: Array<Object>) 
           ^^^^^^^^^^^^^ array type 

这怎么可能是不相容的？它怎么可能是未知的？我明确告诉它的类型。

Answer 1

可以映射对象在followig时尚阵列上

{ 
    event.divisions && 
    event.divisions.edges && 
    event.divisions.edges.map(d => { 
     return d.node.map(division => (
     <div>{division}</div> 
    )) 
    } 

} 

Answer 2

尽量不要做这样的：

{ 
    event.divisions && 
    event.divisions.edges && 
    (event.divisions.edges: $ReadOnlyArray<Object>) 
    .map(d => d.node) 
    .map(division => (
     <div>{division}</div> 
    )) 
}