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mongodb: insert if not exists
... v2.5.4 or there abouts. If you see this message or issue, just get the latest version.
– Kieren Johnstone
May 17 '15 at 20:16
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Java: Check if enum contains a given string?
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This should do it:
public static boolean contains(String test) {
for (Choice c : Choice.values()) {
if (c.name().equals(test)) {
return true;
}
}
return false;
}
This way means you do not have to worry about adding additional enum values ...
LINQ: Not Any vs All Don't
...in fairness, I think they've a bit of a point in that I often find if(!someTest) confusing* when there's an alternative test of equal verbosity and complexity that would return true for the condition we want to act upon. Yet really, I personally find nothing to favour one over the other of the two a...
What is the best JavaScript code to create an img element
...e(1,1); // width, height values are optional params
img.src = 'http://www.testtrackinglink.com';
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How to delete an item in a list if it exists?
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1) Almost-English style:
Test for presence using the in operator, then apply the remove method.
if thing in some_list: some_list.remove(thing)
The removemethod will remove only the first occurrence of thing, in order to remove all occurrences you ...
How do you design object oriented projects? [closed]
...e to develop and check how it looks. These programs will become functional tests of your library when completed.
After this first iteration, you will have a better understanding on how things interact, got out the details and the rough spots, solved issues with a slapped duct tape patch. You are re...
How do I compare two string variables in an 'if' statement in Bash? [duplicate]
...ngimed, [ is a command (actually, an alternate name for the command called test); if you run which [, you'll see there's actually an executable file for it on disk (even though the shell may provide a built-in implementation as a performance optimization). Just like you have to put a space between t...
Does “display:none” prevent an image from loading?
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This answer is only partially correct. I just tested this on Google Chrome (v35) and I can confirm that images with display set to none are not downloaded. This is probably to make responsive design easier on the developer.
– Shawn Whinnery
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How to identify all stored procedures referring a particular table
I created a table on development environment for testing purpose and there are few sp's which are refreing this table. Now I have have to drop this table as well as identify all sp's which are referring this table. I am facing difficulty to find list of all sp's. Please suggest some query by assumin...
Allowed characters in Linux environment variable names
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My quick testing showed that they basically follow the same rules as C variable names do have, namely
a-z, A-Z, _ and 0-9
May NOT begin with a number
So this excludes . inside them. Any illegal variable name is credited with unkno...