Support for Mixed Value Retrieval

[rdohms]

Mixed value, as per phpdoc standard, returns any value without altering it.

• added mixedValue function
• added tests with multiple value types

[codeliner]

@rdohms Thx for your PR 👍 It fixed #2 and I merged it but one question is left open: What should happen when the path exists but the value is NULL and the user has provided a default other than NULL? I tend to return the default in this case (like the other Value methods do) but Mixed include ``NULLas a valid return type so maybe we need to perform anarray_key_exists` check here. What do you think?

[mikemix]

Just a reminder

$array = [
    'key' => null,
];

var_dump(isset($array['key']));

What will be the output? :) Anyway, in my opinion if the requested key does not exist, exception should be thrown. Null should be returned only if the key exists and its value is null.

[codeliner]

@mikemix Thx for the isset hint, array_key_exists seems to be the better choice :-) I ❤️ PHP ... sometimes. I've updated my question accordingly.

if the requested key does not exist, exception should be thrown

Hhm, yeah I think you're right. I've created the array reader to have a tool to inspect unknown arrays without running into errors. Throwing an exception doesn't match that criteria in the first place but when I want to avoid exceptions - well then I have to provide a default. I'll create a new issue to add exceptions.

[rdohms]

Yeah i would agree, throw exceptions, catch and return default if default is set, bubble exception otherwise.

However, i can think of an edge case here also. What if i define a default value of null, how do you know if i have set default or not?

[codeliner]

What if i define a default value of null, how do you know if i have set default or not?

Good catch! This mixedValue method becomes complex 😱

function test_default($default = null) {
    return func_num_args();
}

echo 'No args: ' . test_default() . PHP_EOL;
echo 'With non null default: ' . test_default('foo')  . PHP_EOL;
echo 'With null default: ' . test_default(null)  . PHP_EOL;

//No args: 0
//With non null default: 1
//With null default: 1

... will do the trick

[mikemix]

One can have two readers then: ThrowingExceptionsReader and SilentReader (decorator for the former) 😄