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Problem with converting int to string in Linq to entities
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If you call AsEnumerable you will pay a high performance price on larger databases because it will bring everything in memory. IEnumerable is slower in comparison with IQueryable because the later is executed exclusively in the data...
How to check whether a file or directory exists?
...iven file or directory exists
func exists(path string) (bool, error) {
_, err := os.Stat(path)
if err == nil { return true, nil }
if os.IsNotExist(err) { return false, nil }
return false, err
}
Edited to add error handling.
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Looking for a clear definition of what a “tokenizer”, “parser” and...
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A tokenizer breaks a stream of text into tokens, usually by looking for whitespace (tabs, spaces, new lines).
A lexer is basically a tokenizer, but it usually attaches extra context to the tokens -- this token is a number, that token is a string literal, this other token is a...
Extending an Object in Javascript
... I have one question: how is the Person() constructor being called when you do new Robot()? It seems to me that you should call that base class constructor instead of doing this.name = name; in the Robot() constructor...
– Alexis Wilke
Apr 7 '14 a...
How do I change read/write mode for a file using Emacs?
If a file is set to read only mode, how do I change it to write mode and vice versa from within Emacs?
9 Answers
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Append an object to a list in R in amortized constant time, O(1)?
...irthday. Some kind readers keep repeating any shortcomings with it, so by all means also see some of the comments below. One suggestion for list types:
newlist <- list(oldlist, list(someobj))
In general, R types can make it hard to have one and just one idiom for all types and uses.
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OS X10.9 环境下部署 QT5.3.1 常见的编译问题 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...件中加入对应的SDK版本:
1
QMAKE_MAC_SDK = macosx10.9
3、:-1: error: [ui_mainwindow.h] Trace/BPT trap: 5
dyld: Library not loaded: /work/build/______________________________PADDING______________________________/lib/QtCore.framework/Versio...
Xcode 4 - build output directory
...sdflkjqwergoobledygook. Since I'm building from a script, I'd like to actually find the build (so I can package it and send via TestFlight :) How do I determine which of the many MyAppName-xxxx-s is the right one? Thanks!
– Olie
Oct 2 '14 at 4:02
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Why have header files and .cpp files? [closed]
...dencies so that code that uses the header doesn't necessarily need to know all the details of the implementation and any other classes/headers needed only for that. This will reduce compilation times and also the amount of recompilation needed when something in the implementation changes.
It's not ...
Python Dictionary to URL Parameters
I am trying to convert a Python dictionary to a string for use as URL parameters. I am sure that there is a better, more Pythonic way of doing this. What is it?
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