Struct dprint_swc_ecma_ast_view::Ident

pub struct Ident<'a> {
    pub inner: &'a Ident,
    /* private fields */
}

A complete identifier with span.

Identifier of swc consists of two parts. The first one is symbol, which is stored using an interned string, [JsWord] . The second one is SyntaxContext, which can be used to distinguish identifier with same symbol.

Let me explain this with an example.

let a = 5
{
    let a = 3;
}

In the code above, there are two variables with the symbol a.

Other compilers typically uses type like Scope, and store them nested, but in rust, type like Scope requires [Arc<Mutex>] so swc uses different approach. Instead of passing scopes, swc annotates two variables with different tag, which is named [SyntaxContext]. The notation for the syntax context is #n where n is a number. e.g. foo#1

For the example above, after applying resolver pass, it becomes.

let a#1 = 5
{
    let a#2 = 3;
}

Thanks to the tag we attached, we can now distinguish them.

([JsWord], [SyntaxContext])

See [Id], which is a type alias for this.

This can be used to store all variables in a module to single hash map.

Comparison

While comparing two identifiers, you can use .to_id().

HashMap

There’s a type named [Id] which only contains minimal information to distinguish identifiers.

Fields

inner: &'a Ident

Implementations

impl<'a> Ident<'a>

pub fn to_id(&self) -> Id

pub fn ctxt(&self) -> SyntaxContext

impl<'a> Ident<'a>

pub fn parent(&self) -> Node<'a>

pub fn sym(&self) -> &JsWord

pub fn optional(&self) -> bool

TypeScript only. Used in case of an optional parameter.

Trait Implementations

impl<'a> CastableNode<'a> for Ident<'a>

fn to(node: &Node<'a>) -> Option<&'a Self>

fn kind() -> NodeKind

impl<'a> Clone for Ident<'a>

fn clone(&self) -> Ident<'a>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<'a> From<&'_ Ident<'a>> for Node<'a>

fn from(node: &Ident<'a>) -> Node<'a>

Converts to this type from the input type.

impl<'a> NodeTrait<'a> for Ident<'a>

fn parent(&self) -> Option<Node<'a>>

fn children(&self) -> Vec<Node<'a>>

fn as_node(&self) -> Node<'a>

fn kind(&self) -> NodeKind

fn ancestors(&self) -> AncestorIterator<'a>

fn start_line(&self) -> usize

fn end_line(&self) -> usize

fn start_column(&self) -> usize

fn end_column(&self) -> usize

fn width(&self) -> usize

fn child_index(&self) -> usize

fn previous_sibling(&self) -> Option<Node<'a>>

fn previous_siblings(&self) -> Vec<Node<'a>>

Gets the previous siblings in the order they appear in the file.

fn next_sibling(&self) -> Option<Node<'a>>

Gets the next siblings in the order they appear in the file.

fn next_siblings(&self) -> Vec<Node<'a>>

fn tokens(&self) -> &'a [TokenAndSpan]

fn children_with_tokens(&self) -> Vec<NodeOrToken<'a>>

fn children_with_tokens_fast(
    &self,
    program: &dyn RootNode<'a>
) -> Vec<NodeOrToken<'a>>

fn leading_comments(&self) -> CommentsIterator<'a>

fn trailing_comments(&self) -> CommentsIterator<'a>

fn program(&self) -> Program<'a>

Gets the root node.

fn module(&self) -> &Module<'a>

Gets the root node if the view was created from a Module; otherwise panics.

fn script(&self) -> &Script<'a>

Gets the root node if the view was created from a Script; otherwise panics.

fn text(&self) -> &'a str

fn previous_token(&self) -> Option<&'a TokenAndSpan>

fn next_token(&self) -> Option<&'a TokenAndSpan>

fn previous_tokens(&self) -> &'a [TokenAndSpan]

Gets the previous tokens in the order they appear in the file.

fn next_tokens(&self) -> &'a [TokenAndSpan]

Gets the next tokens in the order they appear in the file.

impl<'a> Spanned for Ident<'a>

fn span(&self) -> Span

Get span of self.