json.at_or_default(key, defaultval)

[adreed-msft]

• Describe the feature in as much detail as possible.

if (j.contains("access_token"))
{
    j.at("access_token").get_to(t.access_token);
} 
else 
{
    t.access_token = "";
}

This tends to be a lot of boilerplate to ensure something's there. I just want to supply a default within the single line if the key does not exist in the json struct.

• Include sample usage where appropriate.

json.at_or_default("nonexistantkey", "default") should return "default", as the key does not exist.

However,

json.at_or_default("existing", "default") // "existing" exists, and contains "nondefault" should return "nondefault" as the key does exist.

[ghost]

Have a a look at value.

https://nlohmann.github.io/json/classnlohmann_1_1basic__json_adcf8ca5079f5db993820bf50036bf45d.html#adcf8ca5079f5db993820bf50036bf45d

[adreed-msft]

Works for me!