javascript - Wrong value in console.log -

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possible duplicate:
is chrome's javascript console lazy evaluating arrays?

i have following snippets in javascript output makes me feel going wrong.

1.

a=2; console.log(a); a+=2; console.log(a);

output:2 4 ; expected

2.

t=[0,2]; console.log(t); t[0]+=2; console.log(t);

output: [2,2] [2,2]

shouldn't output be [0,2] [2,2] ? and whats difference between above 2 cases results in different answers in both cases?

it's because log delayed until chrome has time (i.e. scripts releases cpu).

try understand happens :

var t=[0,2]; console.log(t); settimeout(function() {      t[0]+=2;    console.log(t); }, 1000);

it outputs expect.

is bug of chrome ? maybe side effect of optimization. @ least it's dangerous design...

why there difference ? suppose chrome stores temporarily must log, primary (immutable) value in first case, pointer array in last case.


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