Trait Comments

pub trait Comments {
    // Required methods
    fn add_leading(&self, pos: BytePos, cmt: Comment);
    fn add_leading_comments(&self, pos: BytePos, comments: Vec<Comment>);
    fn has_leading(&self, pos: BytePos) -> bool;
    fn move_leading(&self, from: BytePos, to: BytePos);
    fn take_leading(&self, pos: BytePos) -> Option<Vec<Comment>>;
    fn get_leading(&self, pos: BytePos) -> Option<Vec<Comment>>;
    fn add_trailing(&self, pos: BytePos, cmt: Comment);
    fn add_trailing_comments(&self, pos: BytePos, comments: Vec<Comment>);
    fn has_trailing(&self, pos: BytePos) -> bool;
    fn move_trailing(&self, from: BytePos, to: BytePos);
    fn take_trailing(&self, pos: BytePos) -> Option<Vec<Comment>>;
    fn get_trailing(&self, pos: BytePos) -> Option<Vec<Comment>>;
    fn add_pure_comment(&self, pos: BytePos);

    // Provided methods
    fn with_leading<F, Ret>(&self, pos: BytePos, f: F) -> Ret
       where Self: Sized,
             F: FnOnce(&[Comment]) -> Ret { ... }
    fn with_trailing<F, Ret>(&self, pos: BytePos, f: F) -> Ret
       where Self: Sized,
             F: FnOnce(&[Comment]) -> Ret { ... }
    fn has_flag(&self, lo: BytePos, flag: &str) -> bool { ... }
}

Stores comment.

Implementation notes

Methods uses (&self) instead of (&mut self) for some reasons. Firstly, this is similar to the previous api. Secondly, typescript parser requires backtracking, which requires Clone. To avoid cloning large vectors, we must use Rc<RefCell>. We have two option. We may implement it in the parser or in the implementation. If we decide to go with first option, we should pass Comments to parser, and as a result we need another method to take comments back. If we decide to go with second way, we can just pass [&Comments] to the parser. Thirdly, (&self) allows multi-threaded use-cases such as swc itself.

We use Option instead of no-op Comments implementation to avoid allocation unless required.

Required Methods

fn add_leading(&self, pos: BytePos, cmt: Comment)

fn add_leading_comments(&self, pos: BytePos, comments: Vec<Comment>)

fn has_leading(&self, pos: BytePos) -> bool

fn move_leading(&self, from: BytePos, to: BytePos)

fn take_leading(&self, pos: BytePos) -> Option<Vec<Comment>>

fn get_leading(&self, pos: BytePos) -> Option<Vec<Comment>>

fn add_trailing(&self, pos: BytePos, cmt: Comment)

fn add_trailing_comments(&self, pos: BytePos, comments: Vec<Comment>)

fn has_trailing(&self, pos: BytePos) -> bool

fn move_trailing(&self, from: BytePos, to: BytePos)

fn take_trailing(&self, pos: BytePos) -> Option<Vec<Comment>>

fn get_trailing(&self, pos: BytePos) -> Option<Vec<Comment>>

fn add_pure_comment(&self, pos: BytePos)

Provided Methods

fn with_leading<F, Ret>(&self, pos: BytePos, f: F) -> Ret

where Self: Sized, F: FnOnce(&[Comment]) -> Ret,

fn with_trailing<F, Ret>(&self, pos: BytePos, f: F) -> Ret

where Self: Sized, F: FnOnce(&[Comment]) -> Ret,

fn has_flag(&self, lo: BytePos, flag: &str) -> bool

This method is used to check if a comment with the given flag exist.

If flag is PURE, this method will look for @__PURE__ and #__PURE__.

Implementations on Foreign Types

impl<C> Comments for Option<C>

where C: Comments,

This implementation behaves like NoopComments if it’s None.

fn add_leading(&self, pos: BytePos, cmt: Comment)

fn add_leading_comments(&self, pos: BytePos, comments: Vec<Comment>)

fn has_leading(&self, pos: BytePos) -> bool

fn move_leading(&self, from: BytePos, to: BytePos)

fn take_leading(&self, pos: BytePos) -> Option<Vec<Comment>>

fn get_leading(&self, pos: BytePos) -> Option<Vec<Comment>>

fn add_trailing(&self, pos: BytePos, cmt: Comment)

fn add_trailing_comments(&self, pos: BytePos, comments: Vec<Comment>)

fn has_trailing(&self, pos: BytePos) -> bool

fn move_trailing(&self, from: BytePos, to: BytePos)

fn take_trailing(&self, pos: BytePos) -> Option<Vec<Comment>>

fn get_trailing(&self, pos: BytePos) -> Option<Vec<Comment>>

fn add_pure_comment(&self, pos: BytePos)

fn with_leading<F, Ret>(&self, pos: BytePos, f: F) -> Ret

where Self: Sized, F: FnOnce(&[Comment]) -> Ret,

fn with_trailing<F, Ret>(&self, pos: BytePos, f: F) -> Ret

where Self: Sized, F: FnOnce(&[Comment]) -> Ret,

fn has_flag(&self, lo: BytePos, flag: &str) -> bool

impl<T> Comments for &T

where T: ?Sized + Comments,

fn add_leading(&self, pos: BytePos, cmt: Comment)

fn add_leading_comments(&self, pos: BytePos, comments: Vec<Comment>)

fn has_leading(&self, pos: BytePos) -> bool

fn move_leading(&self, from: BytePos, to: BytePos)

fn take_leading(&self, pos: BytePos) -> Option<Vec<Comment>>

fn get_leading(&self, pos: BytePos) -> Option<Vec<Comment>>

fn add_trailing(&self, pos: BytePos, cmt: Comment)

fn add_trailing_comments(&self, pos: BytePos, comments: Vec<Comment>)

fn has_trailing(&self, pos: BytePos) -> bool

fn move_trailing(&self, from: BytePos, to: BytePos)

fn take_trailing(&self, pos: BytePos) -> Option<Vec<Comment>>

fn get_trailing(&self, pos: BytePos) -> Option<Vec<Comment>>

fn add_pure_comment(&self, pos: BytePos)

fn has_flag(&self, lo: BytePos, flag: &str) -> bool

impl<T> Comments for Box<T>

where T: ?Sized + Comments,

fn add_leading(&self, pos: BytePos, cmt: Comment)

fn add_leading_comments(&self, pos: BytePos, comments: Vec<Comment>)

fn has_leading(&self, pos: BytePos) -> bool

fn move_leading(&self, from: BytePos, to: BytePos)

fn take_leading(&self, pos: BytePos) -> Option<Vec<Comment>>

fn get_leading(&self, pos: BytePos) -> Option<Vec<Comment>>

fn add_trailing(&self, pos: BytePos, cmt: Comment)

fn add_trailing_comments(&self, pos: BytePos, comments: Vec<Comment>)

fn has_trailing(&self, pos: BytePos) -> bool

fn move_trailing(&self, from: BytePos, to: BytePos)

fn take_trailing(&self, pos: BytePos) -> Option<Vec<Comment>>

fn get_trailing(&self, pos: BytePos) -> Option<Vec<Comment>>

fn add_pure_comment(&self, pos: BytePos)

fn has_flag(&self, lo: BytePos, flag: &str) -> bool

impl<T> Comments for Rc<T>

where T: ?Sized + Comments,

fn add_leading(&self, pos: BytePos, cmt: Comment)

fn add_leading_comments(&self, pos: BytePos, comments: Vec<Comment>)

fn has_leading(&self, pos: BytePos) -> bool

fn move_leading(&self, from: BytePos, to: BytePos)

fn take_leading(&self, pos: BytePos) -> Option<Vec<Comment>>

fn get_leading(&self, pos: BytePos) -> Option<Vec<Comment>>

fn add_trailing(&self, pos: BytePos, cmt: Comment)

fn add_trailing_comments(&self, pos: BytePos, comments: Vec<Comment>)

fn has_trailing(&self, pos: BytePos) -> bool

fn move_trailing(&self, from: BytePos, to: BytePos)

fn take_trailing(&self, pos: BytePos) -> Option<Vec<Comment>>

fn get_trailing(&self, pos: BytePos) -> Option<Vec<Comment>>

fn add_pure_comment(&self, pos: BytePos)

fn has_flag(&self, lo: BytePos, flag: &str) -> bool

Implementors

impl Comments for NoopComments

impl Comments for SingleThreadedComments

impl<T> Comments for Arc<T>

where T: ?Sized + Comments,