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String.equals versus == [duplicate]
... caches strings and so something like this would return true. String a = "Hello"; String b = "Hello"; a == b is true even though one would normally expect the result to be false.
– Jon Taylor
Jul 24 '12 at 14:19
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Compiling simple Hello World program on OS X via command line
I've got a simple hello world example that I'm trying to compile on OS X, named hw.cpp :
8 Answers
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Add a property to a JavaScript object using a variable as the name?
...y sort of expression (e.g. a variable) returning a value:
var obj = {
['hello']: 'World',
[x + 2]: 42,
[someObject.getId()]: someVar
}
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Print a string as hex bytes?
I have this string: Hello world !! and I want to print it using Python as 48:65:6c:6c:6f:20:77:6f:72:6c:64:20:21:21 .
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How to convert a string from uppercase to lowercase in Bash? [duplicate]
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If you are using bash 4 you can use the following approach:
x="HELLO"
echo $x # HELLO
y=${x,,}
echo $y # hello
z=${y^^}
echo $z # HELLO
Use only one , or ^ to make the first letter lowercase or uppercase.
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sprintf like functionality in Python
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Python has a % operator for this.
>>> a = 5
>>> b = "hello"
>>> buf = "A = %d\n , B = %s\n" % (a, b)
>>> print buf
A = 5
, B = hello
>>> c = 10
>>> buf = "C = %d\n" % c
>>> print buf
C = 10
See this reference for all supported fo...
Concatenating null strings in Java [duplicate]
...at the bytecode! The compiler takes your code:
String s = null;
s = s + "hello";
System.out.println(s); // prints "nullhello"
and compiles it into bytecode as if you had instead written this:
String s = null;
s = new StringBuilder(String.valueOf(s)).append("hello").toString();
System.out.printl...
How to ignore certain files in Git
I have a repository with a file, Hello.java . When I compile it, an additional Hello.class file is generated.
21 Answers...
Convert object string to JSON
...ou could use eval then JSON.stringify the result. Like this:
var str = "{ hello: 'world', places: ['Africa', 'America', 'Asia', 'Australia'] }";
var json = JSON.stringify(eval("(" + str + ")"));
Note that when you eval an object literal, it has to be wrapped in parentheses, otherwise the braces a...
How to get the number of characters in a std::string?
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If you're using a std::string, call length():
std::string str = "hello";
std::cout << str << ":" << str.length();
// Outputs "hello:5"
If you're using a c-string, call strlen().
const char *str = "hello";
std::cout << str << ":" << strlen(str);
// Out...