javascript - A function with a console log output inside console.log prints undefined - 


function haha(){   console.log('haha'); }  console.log(haha());

prints: 

haha undefined

is because if don't specify return in function return undefined , second console.log outputting?

it returns undefined because function doesn't return anything.

you e.g. return "haha" string or whatever like. 

function haha(){    console.log('haha');    return 'haha';  }    console.log(haha());


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