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Python `if x is not None` or `if not x is None`?
...he if not x is None version to be more clear, but Google's style guide and PEP-8 both use if x is not None . Is there any minor performance difference (I'm assuming not), and is there any case where one really doesn't fit (making the other a clear winner for my convention)?*
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MyISAM versus InnoDB [closed]
... a projects which involves a lot of database writes, I'd say ( 70% inserts and 30% reads ). This ratio would also include updates which I consider to be one read and one write. The reads can be dirty (e.g. I don't need 100% accurate information at the time of read).
The task in question will be ...
JavaScript data grid for millions of rows [closed]
...s set to the total height of all the rows. The rows are still being added and removed as the user is scrolling, but the scrolling itself is done by the browser. That allows it to be very fast yet smooth (onscroll events are notoriously slow). The caveat is that there are bugs/limits in the browse...
Difference between 'struct' and 'typedef struct' in C++?
... It's a holdover from C, in which it makes a difference.
The C language standard (C89 §3.1.2.3, C99 §6.2.3, and C11 §6.2.3) mandates separate namespaces for different categories of identifiers, including tag identifiers (for struct/union/enum) and ordinary identifiers (for typedef and other iden...
What is the difference between LL and LR parsing?
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At a high level, the difference between LL parsing and LR parsing is that LL parsers begin at the start symbol and try to apply productions to arrive at the target string, whereas LR parsers begin at the target string and try to arrive back at the start symbol.
An LL parse i...
Why is iostream::eof inside a loop condition (i.e. `while (!stream.eof())`) considered wrong?
...ndicate, that the next read will be the end of the stream.
Consider this (and assume then next read will be at the end of the stream):
while(!inStream.eof()){
int data;
// yay, not end of stream yet, now read ...
inStream >> data;
// oh crap, now we read the end and *only* now the eo...
Why is there no String.Empty in Java?
I understand that every time I type the string literal "" , the same String object is referenced in the string pool.
11 An...
What is the difference between “int” and “uint” / “long” and “ulong”?
I know about int and long (32-bit and 64-bit numbers), but what are uint and ulong ?
5 Answers
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Simple explanation of clojure protocols
I'm trying to understand clojure protocols and what problem they are supposed to solve. Does anyone have a clear explanation of the whats and whys of clojure protocols?
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PHP and MySQL - how to avoid password in source code? [duplicate]
...configuration file.
Many frameworks use this (Zend, CakePHP, Kohana, etc) and it's the most common way of doing things (even in a non-PHP environment such as ASP.NET with its web.config files). This allows you also to copy over configuration values from environment to environment by just copying th...