User:Keith the Koala/externISBN.js

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function externISBN() {
  if (typeof magicURL=="string" && typeof book_source_URL=="undefined")
  { 
    book_source_URL = magicURL; 
  }

  var magicRegex = /MAGICNUMBER/ig;
  if(mw.config.get('wgPageName') != "Special:BookSources" && !(mw.config.get('wgTitle') == "Book sources" && mw.config.get('wgCanonicalNamespace') == "Project"))
  {
    for (var i = 0; i < document.links.length; i++) 
    {       
      if(document.links[i].href.match(/Special:BookSources\/(.*)/)) 
      {
        document.links[i].href=book_source_URL.replace(magicRegex, RegExp.$1.replace(/[\D]*/g, ''))
      }
    }
  }

}

$(externISBN);