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JavaScript JavaScript Basics (Retired) Introducing JavaScript The JavaScript Console

Posted by john knight
john knight
Courses Plus Student 9,155 Points

question

teacher, i watched your videos about console log . but how do we use console.log syntax we only just type (console.log("start program") (console.log("end program") is this is the use of console.log syntax?

1 Answer

Nick Trabue
PLUS
Nick Trabue
Courses Plus Student 12,666 Points
Nick Trabue
Nick Trabue
Courses Plus Student 12,666 Points 
console.log("string"); //log out this specific string
console.log(variable_name); //log the output of a variable
console.log(2+2) //solve an equation

In your particular example it looks like they were using console log to show when a process started and when it completed. Since javascript runs sequentially it will ensure that if "program end" appears in the console that everything finished running.

function foo() {
   console.log("program started");
   //do things here.
   alert('FOO!');
   //if everything has finished successfully
   console.log("program end");
}

If you don't received program end, you know that something broke down and can begin troubleshooting. I primarily use console.log when troubleshooting to try and figure out where I'm getting stuck or why something isn't working.