I am developing with JavaScript for a while and I am used to a lot of it quirks. But even after years of using this language you still find new curiosities. Today a struggled a while with this one.
Considering this piece of JavaScript code:
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var i = 10;
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function foo() {
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i++; // i is now 11
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console.log("foo1: "+i);
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i = 0; // i is now 0
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console.log("foo2: "+i);
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};
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console.log("global1: "+i); // should be 10
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foo();
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console.log("global2: "+i); // and now 0
Ok. That’s fine. Now we change the code a little bit to this one:
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var i = 10;
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function foo() {
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i++; // is now 11
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console.log("foo1: "+i);
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var i = 0; //create a new variable with value 0
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console.log("foo2: "+i);
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};
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console.log("global1: "+i); // expect: 10
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foo();
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console.log("global2: "+i); // expect: 11
What do you expect? I was quite surprised: continue reading…
