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Count occurrences of a char in a string using Bash
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Building on everyone's great answers and comments, this is the shortest and sweetest version:
grep -o "$needle" <<< "$haystack" | wc -l
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String concatenation: concat() vs “+” operator
...l produces exactly the same code, but the bytecode compiler cheats. Simple testing entirely fails because the entire body of code is thrown away. Summing System.identityHashCode (not String.hashCode) shows the StringBuffer code has a slight advantage. Subject to change when the next update is releas...
How to check if array element exists or not in javascript?
...hey have the prototype method hasOwnProperty "inherited" from Object
in my testing, hasOwnProperty can check if anything exists at an array index.
So, as long as the above is true, you can simply:
const arrayHasIndex = (array, index) => Array.isArray(array) && array.hasOwnProperty(inde...
Difference between “!==” and “==!” [closed]
...imple comparison ( if ($var ==! " ") ) didn't work as expected. After some testing I realized that whoever wrote that code used ==! instead of !== as comparison operator. I've never seen ==! in any language so I wondered how the hell this code could even work and did some testing:
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Get controller and action name from within controller?
...xample of using System.Web.HttpContext static reference)
string sessionTest = System.Web.HttpContext.Current.Session["test"] as string
}
NOTE: likely not the most supported way to access all properties in HttpContext, but for RequestContext and Session it appears to work fine in my application...
Returning an array using C
...ved_from(srcArray[i]);
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}
int main(void)
{
char src[] = "This is a test";
char dst[sizeof src];
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returnArray(src, sizeof src, dst, sizeof dst);
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}
Another method is for the function to allocate the array dynamically and return the pointer and size:
char *returnArray(const ch...
What is the advantage to using bloom filters?
...nts themselves, this is the crucial point. You don't use a bloom filter to test if an element is present, you use it to test whether it's certainly not present, since it guarantees no false negatives. This lets you not do extra work for elements that don't exist in a set (such as disk IO to look the...
C# generic list how to get the type of T? [duplicate]
...>?
Here's the gutsy solution. It assumes you have the actual object to test (rather than a Type).
public static Type ListOfWhat(Object list)
{
return ListOfWhat2((dynamic)list);
}
private static Type ListOfWhat2<T>(IList<T> list)
{
return typeof(T);
}
Example usage:
obje...
Can I target all tags with a single selector?
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This does not work. Please test your code before posting an answer as this is detrimental to anyone who may try using it. I edited your answer with tested and working code.
– Hybrid web dev
Nov 28 '19 at 22:22
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How to make the 'cut' command treat same sequental delimiters as one?
... all the possible combinations for future readers. Explanations are at the Test section.
tr | cut
tr -s ' ' < file | cut -d' ' -f4
awk
awk '{print $4}' file
bash
while read -r _ _ _ myfield _
do
echo "forth field: $myfield"
done < file
sed
sed -r 's/^([^ ]*[ ]*){3}([^ ]*).*/\2/' ...