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HTML

              
                
              
            
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CSS

              
                
              
            
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JS

              
                console.log("=================")
// Your average console.log
console.log("Merry Christmas!")

// Most of the time, we're just interested in quickly logging a value. Why not make that process eight keypresses shorter?
// PS: This will work for any method described below as well.
const log = console.log 
log("All I want for Christmas is to type less!")

// We're about to be logging a lot, so let's put these in a nice group
console.group("Naughty and Nice Children")

// Sometimes you want to log a few aspects of your state at once. Instead of typing something like :
let naughtyChildren = ["Jeff" , "Joel", "Jim" , "John"]
let niceChildren    = ["Jane" , "Jill" , "Jasmine", "Jaqueline"]


log("Naughty Children" , naughtyChildren)
log("Nice Children" , niceChildren)

// You can simply pass multiple arguments to a log. One nice use case for this syntax is comparing values in arrays. (get screen shot) 
log("Naughty Children " , naughtyChildren, "Nice Children " , niceChildren)

// Alas! This is printing all on one line! This is pretty naughty. We should make it nice by using some formatting.
log("Naughty Children \n" , naughtyChildren, "\n Nice Children \n" , niceChildren)

// End our group
console.groupEnd("Naughty and Nice Children");

// Sometimes you would like to see a trace of your function. Console.trace lets you do just that.
console.group("Tracing")
let whoGetsCoalInTheirStocking = 
     names => names.forEach( 
                      name => {
                         log(name, "will get coal in their stocking");
                         console.trace()
                      })
whoGetsCoalInTheirStocking(naughtyChildren);
console.groupEnd("Tracing")


/* 
  Console.dir will let you view an interactive tree of your object.
  In Chrome this happens automatically, but this is helpful for Firefox/Node environments 
*/
let test = {  test1: { passed : true, difficulty: 10 } , 
              test2: { passed : false, difficulty: 6 } ,
              test3: { passed : false, difficulty: 5 } ,
              test4: { passed : true, difficulty: 4 } ,
              test5: { passed : false, difficulty: 9 } , 
              test6: { passed : true, difficulty: 2 }  
           }
console.dir(test);

// Our log is getting too long! Let's clear it out. This might be useful if you get a 
// few errors at the beginning of a page while youre developing. Uncomment to see it in action!
// console.clear();

// Here is a nifty trick to measure time.
console.time('start') 
window.setTimeout( () => {console.timeEnd("start")}, 1000);

/*
  Sometimes you just don't want to see logs anymore, but you're not about to go back 
  through a bunch of code and add some try/catch to everything like you do with all the code you yourself write.
  (ie. maybe a library is throwing an error that you don't find to be too worrisome) 
  One way to handle this situation is to overwrite the console.log method.
  As an added stocking stuffer: 
  If you followed above and saved console.log to a variable (in our case log), you will still get your personal logs!
*/
console.log("Ho ho ho") // Logs

console.log = function(){} // Overwrite console.log function

console.log("Hum hum hum") // Doesn't Log

log("Hum hum hum") // Does Log

console.log("================")
              
            
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999px

Console