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Count table rows
... COUNT(*) is a strict language definition. You will get a parse error if you try COUNT (*) note the space
– ppostma1
Jun 23 '14 at 18:30
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How to test if a string is JSON or not?
...ll, and the server will return either a JSON string with useful data or an error message string produced by the PHP function mysql_error() . How can I test whether this data is a JSON string or the error message.
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How to define static property in TypeScript interface
...() {}
}
Refer to my comment at github issue 13462.
visual result:
Compile error with a hint of static method missing.
After static method implemented, hint for method missing.
Compilation passed after both static interface and normal interface fulfilled.
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Multiple left-hand assignment with JavaScript
... Thanks, this definitely helps. It helps to think in terms of what errors would be thrown if it were evaluated other than right-to-left (in this case, the error would be that var1/var2 are undefined).
– David Calhoun
Nov 19 '09 at 3:48
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What does an exclamation mark mean in the Swift language?
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"forced unwrapping": john! (gives the Person value if it exists, runtime error if it is nil)
"optional binding": if let p = john { println(p) } (executes the println if the value exists)
"optional chaining": john?.learnAboutSwift() (executes this made-up method if the value exists)
I guess you c...
What SOAP client libraries exist for Python, and where is the documentation for them? [closed]
... an infinite loop when opening a WSDL; then python threw a recursion limit error. I found this open ticket regarding the issue: fedorahosted.org/suds/ticket/239 Apparently this was a library breaking bug 3 years ago, and still hasn't been fixed.
– Buttons840
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Is it a good practice to place C++ definitions in header files?
... abomination that is a singleton) as you will run into multiple definition errors. NOTE: C++17's inline variables will make this particular example doable in the future.
As a final point, when using boost as an example of header only code, a huge detail often gets missed.
Boost is library, not use...
How can I know when an EditText loses focus?
I need to catch when an EditText loses focus, I've searched other questions but I didn't find an answer.
5 Answers
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Assign variable in if condition statement, good practice or not? [closed]
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I wouldn't recommend it. The problem is, it looks like a common error where you try to compare values, but use a single = instead of == or ===. For example, when you see this:
if (value = someFunction()) {
...
}
you don't know if that's what they meant to do, or if they intended to...
Creating a temporary directory in Windows?
...y for directories, which makes this much easier, because it does return an error when you attempt to create a directory for the second time. Here is what I use:
[DllImport(@"kernel32.dll", EntryPoint = "CreateDirectory", SetLastError = true, CharSet = CharSet.Unicode)]
[return: MarshalAs(Un...