Associative array .get with .init as default second argument

[Torarin]

2010/10/18 bearophile <bearophileHUGS at lycos.com>:
> In what cases is this useful? Are you able to show me an example of situation where it is useful?
>
> Bye,
> bearophile
>

Bearophile, I probably didn't make it very clear, so I'll try again:

Now:
    if (headers.get("transfer-encoding", "") == "chunked")
More appealing in my opinion:
    if (headers.get("transfer-encoding") == "chunked")

In other words: "Does this key-value pair exist?"

Another example from the HTTP domain:
    if(headers.get("connection", "") == "close")