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django syncdb and an updated model
...tried using South, and after an hour of frustration with obscure migration errors decided to go with Django Evolution instead.
I think it's easier to get started with than South, and it worked perfectly the first time I typed ./manage.py evolve --hint --execute, so I'm happy with it.
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How to check 'undefined' value in jQuery
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Note that typeof always returns a string, and doesn't generate an error if the variable doesn't exist at all.
function A(val){
if(typeof(val) === "undefined")
//do this
else
//do this
}
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What does the question mark operator mean in Ruby?
...a boolean return type so I tried adding them to flag variables, leading to errors. This led to me erroneously believing for a while that there was some special syntax involving ?s.
Relevant: Why can't a variable name end with `?` while a method name can?
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Display number with leading zeros
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x = "%02d.txt" % i raises TypeError (cannot concatenate 'str' and 'int' objects), but x = "%02d.txt" % (i,) does not. Interesting. I wonder where is that documented
– theta
Nov 5 '12 at 18:10
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PHP YAML Parsers [closed]
...e wanted something that was "easy to use, fast, unit tested and had clear error messages."
spyc: YAML parser without dependencies
At the time of this writing, the latest versions release dates for the aforementioned libraries and the versions of the YAML spec (1.2 is the latest version) they sup...
Guid is all 0's (zeros)?
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Right, good point, you will get an error if you use an uninitialized variable, so the value cannot be used.
– JohnD
Nov 2 '11 at 1:35
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Firefox ignores option selected=“selected”
...ause "Attribute autocomplete not allowed on element select at this point." errors on validation.
– Scott
Oct 22 '15 at 18:41
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wait() or sleep() function in jquery?
... is to do .addClass WHEN it completes and is successful, if not .addClass('error') maybe an idea
– Gary Green
Apr 19 '11 at 21:41
52
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Cannot find module cv2 when using OpenCV
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I get "ImportError: numpy.core.multiarray failed to import" when I do this. Any suggestions?
– hiquetj
Feb 6 '17 at 19:11
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Could not find method compile() for arguments Gradle
...e sure that you are editing the correct build.gradle file. I received this error when editing android/build.gradle rather than android/app/build.gradle.
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