47 lines
987 B
Markdown
47 lines
987 B
Markdown
The difference becomes obvious when we look at the code inside a function.
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The behavior is different if there's a "jump out" of `try...catch`.
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For instance, when there's a `return` inside `try...catch`. The `finally` clause works in case of *any* exit from `try...catch`, even via the `return` statement: right after `try...catch` is done, but before the calling code gets the control.
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```js run
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function f() {
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try {
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alert('start');
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*!*
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return "result";
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*/!*
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} catch (err) {
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/// ...
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} finally {
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alert('cleanup!');
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}
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}
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f(); // cleanup!
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```
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...Or when there's a `throw`, like here:
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```js run
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function f() {
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try {
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alert('start');
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throw new Error("an error");
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} catch (err) {
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// ...
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if("can't handle the error") {
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*!*
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throw err;
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*/!*
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}
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} finally {
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alert('cleanup!')
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}
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}
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f(); // cleanup!
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```
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It's `finally` that guarantees the cleanup here. If we just put the code at the end of `f`, it wouldn't run in these situations.
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