`dataclasses` should use `ast` instead of generating code as strings

[KOLANICH]

Feature or enhancement

It uses dynamic code generation and executing of it, but the code itself is generated as a string.

Pitch
May bring the following benefits:

• performance and overhead: no need to parse the code onto AST
• readability and modularity - ast is manipulated as objects
• security - ast classes ctors can be made verifying that the strings used as names don't contain any chars unallowed in the and are not the same as keywords, this way reducing the possibilities to inject malicious code when the names are supplied from untrusted source.

[ericvsmith]

I've implemented this is in the past, and I can assure you that one benefit it will not bring is readability!

But the rest of the points are worth looking at.

[KOLANICH]

and I can assure you that one benefit it will not bring is readability!

One can parse the blocks from source code if one wants to see them as source within source. I did something like that whan I was fixing and improving CoCoPy parser generator. The benefit in readability is that the subgraphs of AST can be and manipulated as objects, this way functions generating code can be decomposed into functions with self-documented names.

[iritkatriel]

I've implemented this is in the past, and I can assure you that one benefit it will not bring is readability!

Another problem is maintenance - changes to the ast will require updating dataclass code. The ast maintainers need to be on board with that.

[ericvsmith]

I'm going to close this. I don't plan on moving to ast manipulation at this time.