Motivation

Currently, parse_param_general handles both the general function parameters and the optional parsing of the self receiver as the first parameter.

This mixes two distinct responsibilities:

• Parsing the self receiver (which has unique grammar and semantics),
• Parsing general parameters (typed, optionally named).

This makes the function harder to understand and harder to test.

What This PR Does

• Moves the parsing of the self parameter out of parse_param_general.
• Handles it explicitly in parse_fn_params before entering the general parameters loop.
• Removes the first_param boolean and its branching logic.
• Keeps req_name as-is (required name enforcement still makes sense).

Behavior After Refactor

Behavior is functionally identical. The only change is structural:

Tests

• Existing parser tests still pass.
• Closure syntax and self receiver handling remain correct.
• No behavioral changes were introduced.

Benefits

• Cleaner separation of concerns: self parsing is specialized and now handled separately.
• Improved readability: General parameters no longer have to reason about self.

Also parsing the self parameter can be extracted into a small inline function to isolate its logic from regular parameter parsing.

Reviewer Notes

• Feel free to suggest if self parsing should be refactored further.
• This cleanup was kept deliberately minimal to avoid breaking existing logic or tests.