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Why can't variable names start with numbers?
...names are "numbers+alpha that don't parse to a valid numeric designation", and that's just silly.
– eaolson
Oct 11 '09 at 3:56
4
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Redis strings vs Redis hashes to represent JSON: efficiency?
...e cases):
Store the entire object as JSON-encoded string in a single key and keep track of all Objects using a set (or list, if more appropriate). For example:
INCR id:users
SET user:{id} '{"name":"Fred","age":25}'
SADD users {id}
Generally speaking, this is probably the best method in most cas...
How do I break a string over multiple lines?
... edited May 30 '19 at 22:23
Alexander Mills
1
answered Sep 24 '10 at 19:54
Matt WilliamsonMatt Williamson
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How do I get the row count of a pandas DataFrame?
I'm trying to get the number of rows of dataframe df with Pandas, and here is my code.
14 Answers
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Does a valid XML file require an XML declaration?
...ere it says it "should" be used -- which means it is recommended, but not mandatory. In XML 1.1, however, the declaration is mandatory. See section 2.8 of the XML 1.1 Recommendation, where it says "MUST" be used. It even goes on to state that if the declaration is absent, that automatically implies ...
Initializing a struct to 0
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The first is easiest(involves less typing), and it is guaranteed to work, all members will be set to 0[Ref 1].
The second is more readable.
The choice depends on user preference or the one which your coding standard mandates.
[Ref 1] Reference C99 Standard 6.7.8...
What is an uninterruptible process?
Sometimes whenever I write a program in Linux and it crashes due to a bug of some sort, it will become an uninterruptible process and continue running forever until I restart my computer (even if I log out). My questions are:
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What is a non-capturing group in regular expressions?
How are non-capturing groups, i.e. (?:) , used in regular expressions and what are they good for?
15 Answers
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How do you specify that a class property is an integer?
I'm experimenting with TypeScript, and in the process of creating a class with an "ID" field that should be an integer, I have gotten a little confused.
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Why historically do people use 255 not 256 for database field magnitudes?
...ric reason why? I assume it's something to do with paging / memory limits, and performance but the distinction between 255 and 256 has always confused me.
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