Parsing_ Benchmarking And Logging — Part 1 MCQs with Explanations

Once you have an API key you should create a separate file to hold all of the configuration information that you will need to share between processes.

The API accepts a total of 8 parameters namely : 1. url 2. location 3. runs 4. fvonly 5. private 6. block 7. f 8. k

The parameter location specifies the agent location, speed and browser to use for the test, formatted as location.browser:location.

If you set fvonly to 1, you get results only for the first view, and do not run the repeat view test.

There are a total of 63 reserved words in JavaScript.

The window.location object can be used to get the current page address (URL) and to redirect the browser to a new page.

The location.assign() method loads a new document.

The setInterval() method will wait a specified number of milliseconds, and then execute a specified function, and it will continue to execute the function, once at every given time-interval.

The clearInterval() method is used to stop further executions of the function specified in the setInterval() method) The clearTimeout() method is used to stop the execution of the function specified in the setTimeout() method.

Hoisting is JavaScript’s default behavior of moving declarations to the top. In JavaScript, a variable can be declared after it has been used) In other words; a variable can be used before it has been declared.

An XML parser converts an XML document into an XML DOM object – which can then be manipulated with JavaScript.

The ActiveXObject() object is used only to instantiate Automation objects, and has no members.

The URL JSON is assumed to reference a file of JSON-formatted data. The value passed to the callback is the object obtained by parsing the URL contents with jQuery.parseJSON(). jQuery.getJSON() uses this type. If the type is “json” and the URL or data string contains “=?”, the type is converted to “jsonp”.

The parse method is defined as Date.parse(datestring) .

The window.print() can be used to print the current page in JavaScript.

The method print() belongs to the window object.

If the radix parameter is omitted, JavaScript assumes the following: 1. If the string begins with “0x”, the radix is 16 (hexadecimal) 2. If the string begins with “0”, the radix is 8 (octal). This feature is deprecated 3. If the string begins with any other value, the radix is 10 (decimal)

If the string begins with 0x, then the radix value will be 16.

The function parseInt() method parses a string and returns an integer.

If the string begins with “0x”, the radix is 16 (hexadecimal).

The radix parameter is used to specify which numeral system to be used, for example, a radix of 16 (hexadecimal) indicates that the number in the string should be parsed from a hexadecimal number to a decimal number.

If the string begins with “0”, the radix is 8 (octal). This feature is deprecated.

The JSON.parse() method parses a string as JSON, optionally transforming the value produced by parsing.

The method parseInt() returns an integer.

The parameters of the method JSON.parse() are : 1. text : The string to parse as JSON. 2. reviver : If a function, prescribes how the value originally produced by parsing is transformed, before being returned.

The radix value will be 10 when the string of the method parseInt() begins with any other value other than 0x and 0.

The method JSON.parse()throws a SyntaxError exception if the string to parse is not valid JSON.

UgilifyJS is a parser, JavaScript Compressor and a beautiful toolkit.

UglifyJS2 is an excellent tool to help you minify your JavaScript! It’s a tried and tested tool, used by libraries such as jQuery.

Acron is the fastest JavaScript parser written in JavaScript which takes only 96.9ms when compared to all the JavaScript parsers available.

There are a total of 7 default number methods in JavaScript namely : 1. constructor() 2. toExponential() 3. toFixed() 4. toLocaleString() 5. toPrecision() 6. toString() 7. valueOf()

The observer effect says that simply observing an act influences its outcome.

There are a couple of ways to benchmark code—either by timing it or by calculating the number of operations performed during execution.

The run time of a code can be calculated as : run time = end time – start time

According to the workflow of a runtime logging, after calculating the run time, decision boxes are kept that will check to either display to the debug screen or log to the server.

The benchmarking process will call the external process. We use XHR object to post the data to the external process.

The external process, say savePerfData should in turn save the results of the test in a flat file.

The function startTimeLogging() is used to start the time logging.

All of the above can be set by using document object in JavaScript.

JavaScript supports lexical scooping that deals with functions instead of blocks.