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What is the difference between “text” and new String(“text”)?
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new String("text");
explicitly creates a new and referentially distinct instance of a String object; String s = "text"; may reuse an instance from the string constant pool if one is available.
You very rarely would ever want to use the new String(anotherString) constru...
How to make lists contain only distinct element in Python? [duplicate]
...g aspect of this new implementation is considered an implementation detail and should not be relied upon". Since they're both based on hashes, I'd think set would be the same, but it's not mentioned, so apparently not: docs.python.org/3.6/whatsnew/3.6.html
– Mark
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Mongod complains that there is no /data/db folder
..., e.g. sudo mkdir -p /data/db
Or you need to do su - to become superuser, and then create the directory with mkdir -p /data/db
Note:
MongoDB also has an option where you can create the data directory in another location, but that's generally not a good idea, because it just slightly complicate...
JavaScript null check
...argument, that argument is always declared even if its value is undefined, and so there won’t be any error. You are right about != null followed by !== undefined being useless, though.
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The relationship could not be changed because one or more of the foreign-key properties is non-nulla
I am getting this error when I GetById() on an entity and then set the collection of child entities to my new list which comes from the MVC view.
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Are class names in CSS selectors case sensitive?
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CSS selectors are generally case-insensitive; this includes class and ID selectors.
But HTML class names are case-sensitive (see the attribute definition), and that's causing a mismatch in your second example. This has not changed in HTML5.1
This is because the case-sensitivity of selecto...
Improving bulk insert performance in Entity framework [duplicate]
I want to insert 20000 records in a table by entity framework and it takes about 2 min. Is there any way other than using SP to improve its performance. This is my code:
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How can I verify if one list is a subset of another?
...answer to your question, however.
A list may contain items multiple times and has a specific order. A set does not. Additionally, sets only work on hashable objects.
Are you asking about subset or subsequence (which means you'll want a string search algorithm)? Will either of the lists be the sam...
How to retrieve a module's path?
...For the file I'm in I had to import another module from the same directory and do as shown here. Does anyone know a more convenient way?
– Ben Bryant
Jan 19 '12 at 18:11
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Why doesn't Python have multiline comments?
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one disadvantage of mix multi-line string and block comments is IDE has no idea what you want thus can't show comment in different style as needed.
– Baiyan Huang
Sep 17 '12 at 3:58
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