User:Lunchboxhero/externISBN.js

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This code will be executed when previewing this page.

Documentation for this user script can be added at User:Lunchboxhero/externISBN.

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

  var magicRegex = /MAGICNUMBER/ig;
  if(wgPageName != "Special:BookSources" && !(wgTitle == "Book sources" && 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);
      }
    }
  }

}

addOnloadHook(externISBN);