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Python concatenate text files
...new file. I could open each file by f = open(...) , read line by line by calling f.readline() , and write each line into that new file. It doesn't seem very "elegant" to me, especially the part where I have to read//write line by line.
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Pretty print in MongoDB shell as default
...y, everything is output to a single line and it's difficult to read, especially with nested arrays and documents.
8 Answers...
How to delete an object by id with entity framework
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The same as @Nix with a small change to be strongly typed:
If you don't want to query for it just create an entity, and then delete it.
Customer customer = new Customer () { Id = id };
context.Customers.Attach(custome...
Real world use cases of bitwise operators [closed]
...checksums, parity, stop bits, flow control algorithms, and so on, which usually depend on the logic values of individual bytes as opposed to numeric values, since the medium may only be capable of transmitting one bit at a time.
Compression, Encryption
Both of these are heavily dependent on bitwise ...
Difference between std::result_of and decltype
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result_of was introduced in Boost, and then included in TR1, and finally in C++0x. Therefore result_of has an advantage that is backward-compatible (with a suitable library).
decltype is an entirely new thing in C++0x, does not restrict only to return type of a function, and is a language fe...
Call a “local” function within module.exports from another function in module.exports?
How do you call a function from within another function in a module.exports declaration?
8 Answers
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What's wrong with nullable columns in composite primary keys?
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Primary keys are for uniquely identifying rows. This is done by comparing all parts of a key to the input.
Per definition, NULL cannot be part of a successful comparison. Even a comparison to itself (NULL = NULL) will fail. This means a key containing NULL would not work.
Additonally, NULL is al...
Passing base64 encoded strings in URL
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en.wikipedia.org/wiki/Base64#URL_applications — it says clearly that escaping ‘makes the string unnecessarily longer’ and mentions the alternate charset variant.
– Michał Górny
Sep 3 '09 at 23:02
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javac is not recognized as an internal or external command, operable program or batch file [closed]
...nal or external command... error message.
In a nutshell, you have not installed Java correctly. Finalizing the installation of Java on Windows requires some manual steps. You must always perform these steps after installing Java, including after upgrading the JDK.
Environment variables and PATH
(...
How can I do an asc and desc sort using underscore.js?
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You can use .sortBy, it will always return an ascending list:
_.sortBy([2, 3, 1], function(num) {
return num;
}); // [1, 2, 3]
But you can use the .reverse method to get it descending:
var array = _.sortBy([2, 3, 1], function(num) {
return num;
});
console.log(array); // [1,...