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Can I replace groups in Java regex?
I have this code, and I want to know, if I can replace only groups (not all pattern) in Java regex.
Code:
7 Answers
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How do you convert a byte array to a hexadecimal string, and vice versa?
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You're using SubString. Doesn't this loop allocate a horrible amount of string objects?
– Wim Coenen
Mar 6 '09 at 16:36
30
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Why are #ifndef and #define used in C++ header files?
...he header is included, it checks if a unique value (in this case HEADERFILE_H) is defined. Then if it's not defined, it defines it and continues to the rest of the page.
When the code is included again, the first ifndef fails, resulting in a blank file.
That prevents double declaration of any iden...
How can I do an asc and desc sort using underscore.js?
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You can use .sortBy, it will always return an ascending list:
_.sortBy([2, 3, 1], function(num) {
return num;
}); // [1, 2, 3]
But you can use the .reverse method to get it descending:
var array = _.sortBy([2, 3, 1], function(num) {
return num;
});
console.log(array); // [1,...
how do you filter pandas dataframes by multiple columns
...r function using query in pandas. Here you have filtering of df results by all the kwargs parameters. Dont' forgot to add some validators(kwargs filtering) to get filter function for your own df.
def filter(df, **kwargs):
query_list = []
for key in kwargs.keys():
query_list.append(f...
To ARC or not to ARC? What are the pros and cons? [closed]
...t has no GC runtime overhead. The compiler inserts retains and releases in all the places you should have anyway. But it's smarter than you and can optimize out the ones that aren't actually needed (just like it can unroll loops, eliminate temporary variables, inline functions, etc.)
OK, now I will...
How to force 'cp' to overwrite directory instead of creating another one inside?
I'm trying to write a Bash script that will overwrite an existing directory. I have a directory foo/ and I am trying to overwrite bar/ with it. But when I do this:
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How to sort an array by a date property
...e a custom non-enumerable sortBy function using a Schwartzian transform on all arrays :
(function(){
if (typeof Object.defineProperty === 'function'){
try{Object.defineProperty(Array.prototype,'sortBy',{value:sb}); }catch(e){}
}
if (!Array.prototype.sortBy) Array.prototype.sortBy = sb;
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How to set Oracle's Java as the default Java in Ubuntu?
...of the JVM, you don't need to update your .bashrc file, it should automatically point to the new version.
If you want to set JAVA_HOME environment variables globally and at system level means use should set in /etc/environment file.
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Python integer incrementing with ++ [duplicate]
...I've looked back at my VB6 days and thought, "What modern language doesn't allow incrementing with double plus signs?":
7 A...