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Start your free trialSeth Lewis
Full Stack JavaScript Techdegree Graduate 18,191 Pointsrgb parens
The code below is refactored to call the randomValue() function on rgb which is assigned to const color.
Why does rgb
require a parens () in order for randomValue() to run? (i. e. rgb( function calls() )
function randomRGB() {
const color = rgb(${randomValue()}, ${randomValue()}, ${randomValue()})
;
return color;
}
1 Answer
Steven Parker
231,172 PointsTo invoke any function (make it run) you place parentheses after its name, whether or not you pass it any arguments inside the parentheses.
This rule is the same in JavaScript and CSS.
Seth Lewis
Full Stack JavaScript Techdegree Graduate 18,191 PointsSeth Lewis
Full Stack JavaScript Techdegree Graduate 18,191 PointsSteve,
Thanks for taking a look at this. To clarify: I was asking about the rgb assigned to const color. Is that what you were addressing? I understand that the function randomRGB requires parens to invoke. I don't see where 'rgb' is a function in the code.
Is that making more sense? Sorry if I'm not being terribly clear. Thanks!
Steven Parker
231,172 PointsSteven Parker
231,172 PointsThe "rgb" used here is a CSS function . It's a built-in standard in the browser. But CSS functions use parentheses in the same way as JavaScript functions. Plus, in this case they also contain 3 arguments (the color values) being passed to the function.
Seth Lewis
Full Stack JavaScript Techdegree Graduate 18,191 PointsSeth Lewis
Full Stack JavaScript Techdegree Graduate 18,191 PointsAh - I see. I don't have much experience with CSS and, as you noted, it was clear to me that I was passing args into the parens. I had heard that CSS utilizes functions but I haven't done that myself. Thank you for clarifying!