fn element_to_node(node: SyntaxElement) -> SyntaxNode {
    match node {
        syntax::NodeOrToken::Node(n) => n,
        syntax::NodeOrToken::Token(t) => t.parent(),
    }
}
/// node or token's parent
node or token's parent
node or token ' s parent
fn element_to_node(node: SyntaxElement) -> SyntaxNode {
    match node {
        syntax::NodeOrToken::Node(n) => n,
        syntax::NodeOrToken::Token(t) => t.parent(),
    }
}
fn element_to_node ( node : SyntaxElement ) -> SyntaxNode { match node { syntax :: NodeOrToken :: Node ( n ) => n , syntax :: NodeOrToken :: Token ( t ) => t . parent ( ) , } }
node or token's parent
node or token ' s parent
node
SyntaxElement
node
SyntaxElement