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Why is it faster to check if dictionary contains the key, rather than catch the exception in case it

... On the one hand, throwing exceptions is inherently expensive, because the stack has to be unwound etc. On the other hand, accessing a value in a dictionary by its key is cheap, because it's a fast, O(1) operation. BTW: The correct way t...
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How does a garbage collector avoid an infinite loop here?

...kes dramatically under 40 seconds per object. That a new object is created and then eligible for finalization is not relevant to the current finalizer. – Jacob Krall Jul 10 '14 at 16:09 ...
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reStructuredText tool support

...re scattered all over the Internet. The official tool list is incomplete and/or outdated, and can be updated only via commit privileges. For some time there was a comprehensive list at the Wikipedia reStructuredText page , but this apparently " did not meet the notability guideline for web conten...
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Differences in auto-unboxing between Java 6 vs Java 7

I have noted a difference in auto unboxing behavior between Java SE 6 and Java SE 7. I'm wondering why that is, because I can't find any documentation of changes in this behavior between these two versions. ...
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How do I exit the Vim editor?

I'm stuck and cannot escape. It says: 10 Answers 10 ...
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When to use Amazon Cloudfront or S3

...to Amazon cloudfront over s3 or the other way around? I'm trying to understand the difference between the 2 through examples. ...
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How to set my phpmyadmin user session to not time out so quickly? [duplicate]

...dmin Session Timeout, open config.inc.php in the root phpMyAdmin directory and add this setting (anywhere). $cfg['LoginCookieValidity'] = <your_new_timeout>; Where <your_new_timeout> is some number larger than 1800. Note: Always keep on mind that a short cookie lifetime is all well ...
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SQL JOIN - WHERE clause vs. ON clause

... JOIN OrderLines ON OrderLines.OrderID=Orders.ID WHERE Orders.ID = 12345 and SELECT * FROM Orders LEFT JOIN OrderLines ON OrderLines.OrderID=Orders.ID AND Orders.ID = 12345 The first will return an order and its lines, if any, for order number 12345. The second will return all orders, but...
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How do I update all my CPAN modules to their latest versions?

...ve method to using upgrade from the default CPAN shell is to use cpanminus and cpan-outdated. These are so easy and nimble to use that I hardly ever go back to CPAN shell. To upgrade all of your modules in one go, the command is: cpan-outdated -p | cpanm I recommend you install cpanminus like th...
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Relation between CommonJS, AMD and RequireJS?

I'm still very confused about CommonJS, AMD and RequireJS , even after reading a lot. 6 Answers ...