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jQuery first child of “this”
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I believe find() searches through all descendants, and :first-child can match one element per parent. Hence, this query can is likely to return several elements. Or am I mistaken?
– Jørn Schou-Rode
Feb 16 '10 at 19:38
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Understanding :source option of has_one/has_many through of Rails
Please help me in understanding the :source option of has_one/has_many :through association. The Rails API explanation makes very little sense to me.
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Asking the user for input until they give a valid response
...put the input method in a while loop. Use continue when you get bad input, and break out of the loop when you're satisfied.
When Your Input Might Raise an Exception
Use try and except to detect when the user enters data that can't be parsed.
while True:
try:
# Note: Python 2.x users s...
How can you set class attributes from variable arguments (kwargs) in python
... constructor (or other function) that takes a variable number of arguments and then sets them as class attributes conditionally.
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Verifying a specific parameter with Moq
I'm starting using Moq and struggling a bit.
I'm trying to verify that messageServiceClient is receiving the right parameter, which is an XmlElement, but I can't find any way to make it work. It works only when I don't check a particular value.
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Can I have multiple :before pseudo-elements for the same element?
...pseudo-element at any time. (This means an element can have both a :before and an :after pseudo-element — it just cannot have more than one of each kind.)
As a result, when you have multiple :before rules matching the same element, they will all cascade and apply to a single :before pseudo-elemen...
How do I parse XML in Python?
I have many rows in a database that contains XML and I'm trying to write a Python script to count instances of a particular node attribute.
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How can I get a file's size in C? [duplicate]
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You need to seek to the end of the file and then ask for the position:
fseek(fp, 0L, SEEK_END);
sz = ftell(fp);
You can then seek back, e.g.:
fseek(fp, 0L, SEEK_SET);
or (if seeking to go to the beginning)
rewind(fp);
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What can I do with a moved-from object?
Does the standard define precisely what I can do with an object once it has been moved from? I used to think that all you can do with a moved-from object is do destruct it, but that would not be sufficient.
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Why aren't variables declared in “try” in scope in “catch” or “finally”?
In C# and in Java (and possibly other languages as well), variables declared in a "try" block are not in scope in the corresponding "catch" or "finally" blocks. For example, the following code does not compile:
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