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saddam lashuel
Courses Plus Student 9,178 PointssetInterval function
What is the difference between A and B please?
function greet(){console.log("hi")} A- setInterval(greet,500); B- setInterval(greet(),500);
1 Answer
Chris Mason
Full Stack JavaScript Techdegree Graduate 24,526 PointssetInterval(greet,500); //runs repeatedly every 0.5 seconds. The timer starts on load.
setInterval(greet(),500); // runs once on load.
When you pass a function with brackets as an argument to another function e.g. `setInterval(greet(), 500) you are passing just the one-time result of the function with the brackets.
When the function is passed as an object reference (without the brackets, only the name of the function) you are passing in what's known as a callback function. See the following vid for more of an idea on callbacks: https://teamtreehouse.com/library/creating-a-simple-callback-function
Some of this answer adapted from: https://stackoverflow.com/questions/15410384/javascript-setinterval-function-with-arguments