PEP 735 – Dependency Groups in pyproject.toml | peps.python.org
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This PEP specifies a mechanism for storing package requirements in pyproject.toml files such that they are not included in any built distribution of the project.

PEP 735 what is it’s goal? Does it solve our dependency hell issue?

A deep dive and out comes this limitation

The mutual compatibility of Dependency Groups is not guaranteed.

– https://peps.python.org/pep-0735/#lockfile-generation

Huh?! Why not?

mutual compatibility or go pound sand!

pip install -r requirements/dev.lock
pip install -r requirements/kit.lock -r requirements/manage.lock

The above code, purposefully, does not afford pip a fighting chance. If there are incompatibilities, it’ll come out when trying randomized combinations.

Without a means to test for and guarantee mutual compatibility, end users will always find themselves in dependency hell.

Any combination of requirement files (or dependency groups), intended for the same venv, MUST always work!

What if this is scaled further, instead of one package, a chain of packages?!

  • Eager EagleEnglish
    3•15 hours ago

    it’s a config file that should be readable and writeable by both humans and tools. So yeah, it makes sense.

    And I don’t lile yaml personally, so that’s a plus to me. My pet peeve is never knowing what names before a colon are part of the schema and which ones are user-defined. Even with strictyaml, reading the nesting only through indentation is harder than in toml.

    • @[email protected]OP
      1•9 hours ago

      You are not wrong, yaml can be confusing.

      Recently got tripped up on sequence of mapping of mapping. Which is just a simple list of records.

      But for the life of me, couldn’t get a simple example working.

      Ended up reversed the logic.

      Instead of parsing a yaml str. Created the sample list of dict and asked strictyaml to produce the yaml str.

      Turns out the record is indented four spaces, not two.

      - file: "great_file_name_0.yml"
    key_0: "value 0"
- file: "great_file_name_1.yml"
    key_0: "value 0"

      Something like ^^. That is a yaml database. It has records, a schema, and can be safely validated!

      The strictyaml documentation covers ridiculously simple cases. There are no practical examples. So it was no help.

      Parser kept complaining about duplicate keys.

      • Eager EagleEnglish
        1•4 hours ago

        It has records, a schema, and can be safely validated!

        uh… a database implies use of a database management system. I don’t think saying that a YAML/TOML/JSON/whatever file is a database is very useful, as these files are usually created and modified without any guarantees.

        It’s not even about being incorrect, it’s just not that useful.