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JavaScript - cannot set property of undefined
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you never set d[a] to any value.
Because of this, d[a] evaluates to undefined, and you can't set properties on undefined.
If you add d[a] = {} right after d = {} things should work as expected.
Alternatively, you could use an object initializer:
d[a] = {
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Is Ruby pass by reference or by value?
@user object adds errors to the lang_errors variable in the update_lanugages method.
when I perform a save on the @user object I lose the errors that were initially stored in the lang_errors variable.
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Entity Framework - Invalid Column Name '*_ID"
I've narrowed this down to some issue between Code First and Database first EF, but I'm not sure how to fix it. I'll try to be as clear as I can, but I honestly am missing some of the understanding here myself. This is Entity Framework 4.4
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What does enctype='multipart/form-data' mean?
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When you make a POST request, you have to encode the data that forms the body of the request in some way.
HTML forms provide three methods of encoding.
application/x-www-form-urlencoded (the default)
multipart/form-data
text/plain
Work was being done on adding application/json, but that has...
How to get line count of a large file cheaply in Python?
...(hundreds of thousands of lines) in python. What is the most efficient way both memory- and time-wise?
40 Answers
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+ operator for array in PHP?
...e right-hand array appended to the left-hand array; for keys that exist in both arrays, the elements from the left-hand array will be used, and the matching elements from the right-hand array will be ignored.
So if you do
$array1 = ['one', 'two', 'foo' => 'bar'];
$array2 = ['three'...
Strings are objects in Java, so why don't we use 'new' to create them?
We normally create objects using the new keyword, like:
15 Answers
15
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How do you use “
I just finished reading about scoping in the R intro , and am very curious about the <<- assignment.
6 Answers
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Comma in C/C++ macro
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Because angle brackets can also represent (or occur in) the comparison operators <, >, <= and >=, macro expansion can't ignore commas inside angle brackets like it does within parentheses. (This is also a problem...
Are HLists nothing more than a convoluted way of writing tuples?
...e, and more generally, to identify canonical use cases where HLists cannot be used (or rather, don't yield any benefits over regular lists).
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