Get info about Link to Dynamic Link Table

I have one problem. I have two Doctypes, A and B. Inside Doctype A i have table in which on each row i link few docnames of doctype B.
When i go to some docname of doctype B and click on Menu->Links i can see on dialog the docname of doctype A in which i linked docname of doctype B.
I would like to create inside every docname of Doctype B the table with dynamic links in which i will see the same info which i can see in Menu->Links.
How to do that? I know that everything about Menu->Links is doing by code in apps\frappe\frappe\public\js\frappe\form\linked_with.js but i really don’t know how to “copy” this info to table of dynamic links.
How this Menu->Links knows every links of Doctype B? I tried also get some information in sql database from doctype B table, but no info inside database fields …
I hope I have made it clear what I mean and please for any tips/advice.

Could someone help?

ok… found it …

			if(!frm.linked_with) {
				frm.linked_with = new frappe.ui.form.LinkedWith({
					frm: frm

Now, inside frappe-bench\apps\frappe\frappe\public\js\frappe\form\linked_with.js i would like to add the content from Links to Dynamic Link table and got the error in console:

TypeError: frappe.ui.form.LinkedWith is not a constructor
    at Object.callback (eval at setup (form.min.js?ver=1520612983.0:2693), <anonymous>:19:24)
    at Object.callback [as success_callback] (desk.min.js?ver=1520612983.0:1486)
    at _ (desk.min.js?ver=1520612983.0:1510)
    at Object.<anonymous> (desk.min.js?ver=1520612983.0:1611)
    at i (jquery.min.js:2)
    at Object.fireWith [as resolveWith] (jquery.min.js:2)
    at z (jquery.min.js:4)
    at XMLHttpRequest.<anonymous> (jquery.min.js:4)

Code inside linked_with.js:

		const linked_docs = this.frm.__linked_docs;
		 Object.keys(linked_docs).map(dt => {		 
					linked_docs[dt].map(value => {
						this.frm.add_child('links', {
							link_doctype: dt,

I would like also to add that sometimes this code works, i.e. i can see the links in Dynamic Link Table, but sometime it’s just showing this error and can’t see anything … even button “Links” not works…
Could anyone help?