index.js
function concatenate(node, index, parent) {
        if (
            parent &&
            (parent.type === 'ParagraphNode' || parent.type === 'RootNode') &&
            queue.indexOf(parent) === -1
        ) {
            queue.push(parent);
        }
    }
function concatenate(node, index, parent) {
        if (
            parent &&
            (parent.type === 'ParagraphNode' || parent.type === 'RootNode') &&
            queue.indexOf(parent) === -1
        ) {
            queue.push(parent);
        }
    }
function concatenate ( node , index , parent ) { if ( parent && ( parent . type === 'ParagraphNode' || parent . type === 'RootNode' ) && queue . indexOf ( parent ) === - 1 ) { queue . push ( parent ) ; } }
Gather a parent if not already gathered.

@param {NLCSTChildNode} node - Child.
@param {number} index - Position of `node` in
`parent`.
@param {NLCSTParentNode} parent - Parent of `child`.
Gather a parent if not already gathered .