包装Javascript-值得吗？

Question

If a packed Javascript saves 20kb off the download size, but takes a perfomance hit to unpack, then are there any benefits, besides obfuscating the code?

I've made this a community wiki because it may be open to some discussion.

Answer 1

Packed javascript code generally does not take longer to execute vs regular code. Most code packers will shorten variables, function names and use a host of tricks to make the source smaller. The resulting source is fully executable! You can verify this by taking a look at it during runtime with firebug. You'll see the compressed code executing in its minimized form.

Answer 2

简短的回答，是的，因为客户端计算机的拆包时间比传输速度快，并且互联网本身也过载，所以任何使事情变得更好的贡献都受到匿名的赞赏，还请记住，大多数客户端将缓存这些东西，并且更大的客户端归档文件的机会越大，它就会从客户端缓存中撤出自身或其他内容，尤其是在移动设备中

Answer 3

Presumably, packed JavaScript is (slightly) more efficient for the server to send, while the unpacking expense is absorbed by the client.

If the user experience is equivalent in both cases, I'd go for the packed JS.

Anytime you can push some work to the client without incurring a negative user experience, go for it, and reap the benefits of distributed computing.

Answer 4

The guys at Yahoo's YSlow recommend using both a minifier and gzip compression.

The minifier will strip out whitespace, shorten variable names etc. That way you can code with proper indentation and variable names so that other developers can understand your code.

The gzip compression is probably even more valuable.

Answer 5

The question is, why does the packing save 20kB? You should investigate making your 'normal' javascript smaller. Is the readability of your code significantly improved by putting spaces around operators, or by using very long variable and function names? The most egregious waste of bandwidth I have seen on any web content, script or page or css, is indenting with spaces. If you must indent, use tabs, or single spaces. Nothing is more wasteful than a hundred lines in a row with 20+ spaces at the beginning.