has
check if a dict has a given key, or a list has a given index
(any xs, any key) -> boolean
If xs is a dict, casts key to string and returns whether key is a key in xs.
If xs is a list, casts key to long and returns whether key is an existing index in xs.
Returns nil if xs is nil.
Throws an error if xs is not a list or dict.
Parameters
| Name | Type | Description |
|---|---|---|
xs |
dict or list | The dict or list to check |
key |
string or long | The key or index to access |