javascript - How the symbol $ in jquery works? -

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this question has answer here:

how can jquery run function when ever sees $ in script file? $ not javascript key character how come when ever $ appear, jquery run function? need read script file in way eval it? possible remake symbol?

the jquery javascript file has following line in it:

window.jquery = window.$ = jquery;

meaning window-scoped $ variable assigned jquery namespace, in jquery functions placed under. why can use jquery in code $.

you same method , character symbol, even:

window.$$ = jquery;

would mean jquery assigned $$, etc.


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