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noprint

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\n \n $\"\"$ \n

\n","type":"blockquote","key":"bc7pm"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[{"length":36,"offset":0,"style":"BOLD"}],"text":"Предварительная загрузка изображений","type":"header-three","key":"4ci45"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[],"text":"Чтобы предварительно загрузить большое количество изображений и избежать белого экрана:","type":"unstyled","key":"cmgqq"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[],"text":"const images = []\nfunction preloader(args) {\n for (let i = 0, len = args.length; i < len; i++) { \n images[i] = new Image() \n images[i].src = args[i]\n } \n} \npreloader(['1.png', '2.jpg'])","type":"blockquote","key":"60dlc"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[],"text":"JS","type":"header-three","key":"e6iae"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[{"length":27,"offset":0,"style":"BOLD"}],"text":"Создание строковых скриптов","type":"header-three","key":"2jbbp"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[],"text":"Чтобы преобразовать строку/строки в js-скрипт (этот метод отличается xss-уязвимостью, поэтому требует осмотрительности):","type":"unstyled","key":"3a3j5"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[],"text":"const obj = eval('({ name: \"jack\" })')\n// obj будет преобразован в object{ name: \"jack\" }\nconst v = eval('obj')\n// v станет переменной obj","type":"blockquote","key":"7gk0e"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[{"length":35,"offset":0,"style":"BOLD"}],"text":"Разделение имен рекурсивной функции","type":"header-three","key":"3pm86"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[],"text":"Чтобы после изменения имени рекурсивной функции изменить внутреннее имя функции (argument — это внутренний объект функции, включающий все параметры, переданные в функцию, а arguments.callee представляет имя функции):","type":"unstyled","key":"9tji5"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[],"text":"// Это базовая последовательность Фибоначчи\nfunction fibonacci (n) {\n const fn = arguments.callee\n if (n <= 1) return 1\n return fn(n - 1) + fn(n - 2)\n}","type":"blockquote","key":"emet0"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[],"text":"DOM-элементы","type":"header-three","key":"cur2f"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[{"length":38,"offset":0,"style":"BOLD"}],"text":"Проверка неявно определенного элемента","type":"header-three","key":"fgh99"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[],"text":"Чтобы определить, появляется ли DOM-элемент в данный момент в представлении страницы, используйте IntersectionObserver:","type":"unstyled","key":"843i5"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[],"text":"\n\n

Invisible

\n","type":"blockquote","key":"k580"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[{"length":27,"offset":0,"style":"BOLD"}],"text":"Редактирование DOM-элемента","type":"header-three","key":"693ag"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[],"text":"Чтобы отредактировать DOM-элемент, кликните на него, как на текстовую область:","type":"unstyled","key":"ecmlh"},{"data":{},"depth":0,"entityRanges":[],"inlineStyleRanges":[],"text":"

here can be edited

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test

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