Javascript variable scope - variable undefined -

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• global javascript variable scope: why doesn't work? 5 answers

i trying understand how following java script code works. have global variable called color stores 'blue'; calling printcolor() simple prints color. don't understand why color undefined when defining new local variable called color in function. if uncomment local color variable declaration below, color undefined.

var color = 'blue';  printcolor();  function printcolor(){   document.write(color);   //var color = "green"; } 

you re-declaring variable color inside printcolor() function, since declaration hoisted top overwrites @ start of function, hence see undefined

var color = 'blue';  function printcolor(){   document.write(color);   //var color = "green"; } printcolor(); 

but if do:

function printcolor(){     document.write(color); //undefined     var color = "green";     console.log(color); //shows green }