Get the url-sheet from an other cell in Importrange

I am looking for a way to change the url in an importrange without actually opening the formula, but just changing the url in an other cell.I tried with putting the cell reference, with the hyperlink function, with or without ".", but it doesn't work. Is it something that can be done ?

I am looking for a formula that can do this :

=Importrange(get link in cell A2;"TAB!B1:B1")