In JavaScript, does it make a difference if I call a function with parentheses? -


i noticed difference when calling function empty parentheses, or without parentheses @ all. however, not passing arguments function wondered, difference between:

window.onload = initall();

and

window.onload = initall;

please explain principle behind it.

window.onload = initall();

this executes initall() straight away , assigns function's return value window.onload. not want. initall() have return function make sense.

window.onload = initall;

this assigns actual function window.onload - possible because in javascript, @felix says, functions first class objects - without executing it. initall executed load event.


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