Unless I didn't understand well, this has been tried in #20738 and abandoned.

Hum, that's not exactly the same - then I have an objection: the class is not usable anymore without Symfony's DIC, which is the one supposed to resolve the %app_locales%.
An annotation would be better, by providing decoupling.

What about using named arguments like that?

services:
    AppBundle\Controller\:
        resource: '../../src/AppBundle/{EventListener,Form/Type,Security,Twig,Utils}'
        arguments:
            $locales: '%app_locales%'
            $sender: '%app.notifications.email_sender%'

Oops looks like it's not possible... Maybe we should allow it then?

@GuilhemN see https://github.com/symfony/symfony/projects/2#card-1770476 - which to be made to work should apply these conditionally

What do you mean by "conditionally"?

Dunno yet, this is only a project card, needs more thought :)
We could also handle a conditional syntax, eg. $?locales: '%app_locales%'

Ok I'll give it a try, seems great :)

While this may seem like a nice solution, there's a few drawbacks:

• What if you want an int? You'll never be able to type-hint that
• What if the value was not found with auto-wiring? I will end up with %app_locales%

public function __construct(Markdown $parser, $locales = '%app_locales%');

What about a custom annotation?

Makes sense? It's something that I can't see against using annotation for this?

@magarzon I'm not a fond of using (non-standard) annotations for DI: #21103 (comment)

But while this PR is nice, I don't like having to add Symfony specific syntaxes ('%locales%') in the code itself, the code (especially in a service) should be framework agnostic. From that POV, #20738 is better (IMO).

With bold news in Symfony 3.3 like PSR-4 service autodiscovery, I think this makes more sense to current coding context now.

Why? Because I cannot use this awesome PSR-4 autodiscovery on most of my services :(

Instead, I have to write them manually all one by one.

parameters:
    twitter_name: 'VotrubaT'
    site_ur: 'https://tomasvotruba.com'
    source_directory: '%kernel.project_dir%/../../../source'
    minimal_gap_in_days: 4 # how many days to wait before publishing another Tweet

    twitter_consumer_key: "..."
    twitter_consumer_secret: "..."
    twitter_oauth_access_token: "..."
    twitter_oauth_access_token_secret: "..."

services:
    TomasVotruba\Website\TweetPublisher\PostTweetsProvider:
        arguments:
            - '%site_url%'
            - '%source_directory%'

    TomasVotruba\Website\TweetPublisher\PostsProvider:
        arguments:
            - '%source_directory%'

    TomasVotruba\Website\TweetPublisher\TwitterApi\TwitterApiWrapper:
        arguments:
            - '%twitter_name%'

    TomasVotruba\Website\TweetPublisher\TweetPublisher:
        public: true # for bin/tweet-new-posts container fetch
        arguments:
            - '%minimal_gap_in_days%'

    # Twitter API
    TomasVotruba\Website\TweetPublisher\TwitterApi\TwitterApiFactory:
        arguments:
            - '%twitter_consumer_key%'
            - '%twitter_consumer_secret%'
            - '%twitter_oauth_access_token%'
            - '%twitter_oauth_access_token_secret%'

I'd love something like this

• explicit
• time-saving
• typo-proof
• make use of PSR-4 way

services:
    _defaults:
        autowire_parameters: true

    TomasVotruba\Website\TweetPublisher\:
        resource: ../

What do you think?

You can already use bindings https://symfony.com/blog/new-in-symfony-3-4-local-service-binding
Or use the parameter bag as a service in 4.1 since #25288.

Wow, thanks! 👏

I never thought that could be used this way, even though I've read the post.

Also ParamBag as service is great, I have the same bundle for ages 👍

I forgot to share a compiler pass that adds this feature
https://www.tomasvotruba.cz/blog/2018/11/05/do-you-autowire-services-in-symfony-you-can-autowire-parameters-too/