Add ternary conditional operator (?:) and $-prefix None-declaration syntax

[RAJ0793]

Feature or enhancement

Proposal:

Motivation

Python's existing x if cond else y ternary requires more characters and
some developers coming from C-family languages find cond ? x : y more
concise for simple one-line conditionals. Additionally, a $name shorthand
for declaring a variable pre-initialized to None (similar to Dart's
declaration semantics) could reduce boilerplate for patterns like:

x = None
...
x = some_value

Proposed syntax

$name              # equivalent to: name = None
cond ? a : b        # equivalent to: a if cond else b

Current status

I have a working prototype implemented at the grammar level
(Grammar/python.gram) as a proof of concept, tested against CPython's
own PEG parser generator, covering: precedence, nested ternaries,
list/dict/set comprehensions, generator expressions, lambda, walrus,
keyword arguments — with one known issue (f-string compatibility)
still being investigated.

Branch: https://github.com/RAJ0793/cpython/tree/features-clean

Questions for the community

1. Is there existing prior art / rejected PEPs covering this exact syntax?
2. Would this need a formal PEP given it's new operator syntax?
3. Is there appetite for this kind of shorthand in the language, or does
   it conflict with "there should be one obvious way to do it"?

I'm a newer contributor and want to follow the right process — happy to
close this if it's already been discussed and rejected before.

Has this already been discussed elsewhere?

No response given

Links to previous discussion of this feature:

No response

Linked PRs

• gh-155087: Add ternary conditional operator (?:) and $-prefix None-declaration syntax #155089

[JelleZijlstra]

This is not something that should be discussed in an issue; it requires a PEP. I don't recall a PEP proposing either of your suggested features. I'd suggest separating the two as they are not directly related and starting with a post in the "Ideas" category on discuss.python.org.

Personally I'd give this proposal a low chance of being accepted, but if you want to push this forward, go ahead.

[RAJ0793]

This is not something that should be discussed in an issue; it requires a PEP. I don't recall a PEP proposing either of your suggested features. I'd suggest separating the two as they are not directly related and starting with a post in the "Ideas" category on discuss.python.org.

Personally I'd give this proposal a low chance of being accepted, but if you want to push this forward, go ahead.

This is not something that should be discussed in an issue; it requires a PEP. I don't recall a PEP proposing either of your suggested features. I'd suggest separating the two as they are not directly related and starting with a post in the "Ideas" category on discuss.python.org.

Personally I'd give this proposal a low chance of being accepted, but if you want to push this forward, go ahead.

Thank you very much for taking the time to reply and for pointing me in the right direction.

This is my first contribution to CPython, so I wasn't aware that language syntax proposals need to go through the PEP process before opening an issue or a PR. Your feedback helped me understand that, and I genuinely appreciate it.

I'll take your advice and learn more about the process, including discuss.python.org and the PEP workflow, before proposing language changes again. I'll also separate unrelated ideas in the future.

I'm looking forward to contributing more to Python. Even if many of my future contributions or proposals are rejected, I'll continue learning from the feedback, improving my work, and contributing wherever I can. Every review teaches me something valuable.

Thank you again for your guidance.