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What is the proper way to check for null values?
...rogram. I'd rather use a safe cast because I think it's likely to surface errors faster. It also avoids calling ToString() on a string object.
– tvanfosson
Mar 20 '12 at 19:17
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Convert JavaScript String to be all lower case?
...ying toLowerCase or toLocaleLowerCase on null would yield null (and not an error condition).
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Fastest way to find second (third…) highest/lowest value in vector or column
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I used this method, but get the following error: Error in sort.int(x, na.last = na.last, decreasing = decreasing, ...) : index 4705 outside bounds Any idea what might the issue be? Some details: My x is a numeric vector of length 4706 with some NAs in the data. I...
Create an empty object in JavaScript with {} or new Object()?
...t be a good practice to get into.
One other thing: you might have subtle errors if you forget to use the new operator. So, using literals will help you avoid that problem.
Ultimately, it will depend on the situation as well as preference.
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Does MySQL index foreign key columns automatically?
... as being a "redundant index". I tried to drop it but I got the following error: "ERROR 1553 (HY000): Cannot drop index 'index_name': needed in a foreign key constraint". So, it's not possible to drop that index and keep the foreign key.
– Ciprian Stoica
Oct ...
What represents a double in sql server?
... With some quick and dodgy mental arithmetic... the rounding/approximation errors would be the about the length of this fill stop -> "."
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iFrame src change event detection?
...);
https://jquery.com/upgrade-guide/3.0/#breaking-change-load-unload-and-error-removed
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Arrow operator (->) usage in C
...ointer has no members! And compiler knows this and will therefore issue an error e.g.:
error: ‘ptr’ is a pointer; did you mean to use ‘->’?
printf("%d\n", *ptr.km);
Instead you use this (*ptr).kg and you force compiler to 1st dereference the pointer and enable acess to the chunk of d...
When would you use the different git merge strategies?
...the default 'recursive' for a two-head merge that had fatal git-write-tree errors. 'Resolve' strategy merged cleanly. It may have had to do with moving a lot of files around in the branch being merged.
– thaddeusmt
May 17 '12 at 12:51
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How to replace strings containing slashes with sed?
... contains the actual delimiter used by sed - then sed terminates on syntax error. Consider the following example:
This works:
$ VALUE=12345
$ echo "MyVar=%DEF_VALUE%" | sed -e s/%DEF_VALUE%/${VALUE}/g
MyVar=12345
This breaks:
$ VALUE=12345/6
$ echo "MyVar=%DEF_VALUE%" | sed -e s/%DEF_VALUE%/${V...