Symfony\Component\OptionsResolver\OptionsResolverInterface

Sets default option values.

The options can either be values of any types or closures that
evaluate the option value lazily. These closures must have one
of the following signatures:

<code>
function (Options $options)
function (Options $options, $value)
</code>

The second parameter passed to the closure is the previously
set default value, in case you are overwriting an existing
default value.

The closures should return the lazily created option value.

Replaces default option values.

Old defaults are erased, which means that closures passed here cannot
access the previous default value. This may be useful to improve
performance if the previous default value is calculated by an expensive
closure.

Sets optional options.

This method declares valid option names without setting default values for them.
If these options are not passed to {@link resolve()} and no default has been set
for them, they will be missing in the final options array. This can be helpful
if you want to determine whether an option has been set or not because otherwise
{@link resolve()} would trigger an exception for unknown options.

Sets required options.

If these options are not passed to {@link resolve()} and no default has been set for
them, an exception will be thrown.

Sets allowed values for a list of options.

Adds allowed values for a list of options.

The values are merged with the allowed values defined previously.

Sets allowed types for a list of options.

Adds allowed types for a list of options.

The types are merged with the allowed types defined previously.

Sets normalizers that are applied on resolved options.

The normalizers should be closures with the following signature:

<code>
function (Options $options, $value)
</code>

The second parameter passed to the closure is the value of
the option.

The closure should return the normalized value.

Returns whether an option is known.

An option is known if it has been passed to either {@link setDefaults()},
{@link setRequired()} or {@link setOptional()} before.

Returns whether an option is required.

An option is required if it has been passed to {@link setRequired()},
but not to {@link setDefaults()}. That is, the option has been declared
as required and no default value has been set.

Returns the combination of the default and the passed options.