- Use typed enum for line_data callback. - Pass in 'const' arguments where possible. - Use 'r_' prefix for return arguments. - Remove unused return value from line_get callback. - Remove redundant casts.
- Use typed enum for line_data callback. - Pass in 'const' arguments where possible. - Use 'r_' prefix for return arguments. - Remove unused return value from line_get callback. - Remove redundant casts.