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Any reason not to use '+' to concatenate two strings?
A common antipattern in Python is to concatenate a sequence of strings using + in a loop. This is bad because the Python interpreter has to create a new string object for each iteration, and it ends up taking quadratic time. (Recent versions of CPython can apparently optimize this in some cases, b...
What is the difference between substr and substring?
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The difference is in the second argument. The second argument to substring is the index to stop at (but not include), but the second argument to substr is the maximum length to return.
Links?
https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/String/substr
https://develop...
Is there a performance gain in using single quotes vs double quotes in ruby?
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Benchmark.bm(15) do |x|
x.report("assign single") { n.times do; c = 'a string'; end}
x.report("assign double") { n.times do; c = "a string"; end}
x.report("concat single") { n.times do; 'a string ' + 'b string'; end}
x.report("concat double") { n.times do; "a string " + "b string"; end}
en...
Java equivalent to Explode and Implode(PHP) [closed]
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The Javadoc for String reveals that String.split() is what you're looking for in regard to explode.
Java does not include a "implode" of "join" equivalent. Rather than including a giant external dependency for a simple function as the other...
What's the simplest way to print a Java array?
In Java, arrays don't override toString() , so if you try to print one directly, you get the className + '@' + the hex of the hashCode of the array, as defined by Object.toString() :
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PHP - concatenate or directly insert variables in string
I am wondering, What is the proper way for inserting PHP variables into a string?
This way:
14 Answers
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Java String to SHA1
I'm trying to make a simple String to SHA1 converter in Java and this is what I've got...
12 Answers
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How to overcome TypeError: unhashable type: 'list'
...b'x') (which makes sure you are splitting the byte with the proper type of string). You can also open the file using with open('filename.txt', 'rU') as f: (or even with open('filename.txt', 'r') as f:) and it should work fine.
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How to join int[] to a character separated string in .NET?
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var ints = new int[] {1, 2, 3, 4, 5};
var result = string.Join(",", ints.Select(x => x.ToString()).ToArray());
Console.WriteLine(result); // prints "1,2,3,4,5"
EDIT: As of (at least) .NET 4.5,
var result = string.Join(",", ints.Select(x => x.ToString()).ToArray());
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Swift: declare an empty dictionary
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var emptyDictionary = [String: String]()
var populatedDictionary = ["key1": "value1", "key2": "value2"]
Note: if you are going to change the contents of the dictionary over time then declare it as a var (variable). You can declare an empty ...