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is_null($x) vs $x === null in PHP [duplicate]
					...someone strongly suggested that I use  is_null()  instead as it is specifically designed for the null-evaluation purpose.  He also started talking about math or something.
                    
                    
                        
                            
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							How to find where gem files are installed
					I can finds gems that are installed using  gem list , but it doesn't show me where the gems are installed.
                    
                    
                        
                            
                                
                                        10 Answers
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							将Linux代码移植到Windows的简单方法 - 操作系统(内核) - 清泛网 - 专注C/C++及内核技术
					...(Header File)的包含问题。在Config.h中定义了很多类似HAVE_XXXX_H。比如定义HAVE_CONFIG_H为1表示工程中可以使用config.h。
#define HAVE_MALLOC_H 1表示可以在工程中使用Malloc.h头文件。通过调整这些定义值,可以去除一些Windows平台下面没有...				
				
				
							Count Rows in Doctrine QueryBuilder
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                He accepted your answer so I guess all is well.  I was under the impression that he only wanted a count without the overhead of actually retrieving the rows which my example shows.  There is of course no reason why where conditions could not be added.
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							Read url to string in few lines of java code
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                Just don't forget you need to call Scanner#close() later.
                
– Marcelo
                Dec 21 '12 at 3:55
            
        
    
    
        
            
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							Difference between del, remove and pop on lists
					...gt;>> a = [4, 5, 6]
>>> a.remove(7)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: list.remove(x): x not in list
>>> del a[7]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
IndexError: lis...				
				
				
							Numpy first occurrence of value greater than existing value
					... about why it gives the correct result despite the original intent not actually seeking a maximum, not why it is faster as I cannot claim to understand the inner details of argmax.
                
– askewchan
                Oct 8 '14 at 14:24
                        
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							What's Mongoose error Cast to ObjectId failed for value XXX at path “_id”?
					...ng a request to  /customers/41224d776a326fb40f000001  and a document with  _id   41224d776a326fb40f000001  does not exist,  doc  is  null  and I'm returning a  404 :
                    
                    
                        
                            
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							How do I use Ruby for shell scripting?
					...r, options)
rm(list, options)
rm_r(list, options)
rm_rf(list, options)
install(src, dest, mode = <src's>, options)
chmod(mode, list, options)
chmod_R(mode, list, options)
chown(user, group, list, options)
chown_R(user, group, list, options)
touch(list, options)
Which is pretty nice 
    
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							How to resolve “must be an instance of string, string given” prior to PHP 7?
					... supposed to work to begin with. Given the dynamic typing system, this actually makes some sort of perverted sense.
You can only manually "type hint" scalar types:
function foo($string) {
    if (!is_string($string)) {
        trigger_error('No, you fool!');
        return;
    }
    ...
}
    
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