square-bracket

I have the following class: class risc { // singleton protected: static unsigned long registers[8]; public: unsigned long operator [](int i) { return registers[i]; } }; as you can see I've implemented the square brackets operator for "getting". Now I would like to implement it for setting, i.e.: risc[1] = 2 . How can it be done? Try this: class risc { // singleton protected: static unsigned long registers[8]; public: unsigned long operator [](int i) const {return registers[i];} unsigned long & operator [](int i) {return registers[i];} }; You need to return a reference from your operator[] so

I'm trying to understand the difference between the Dot and the Square Bracket Notation. While going through various examples here on SO and on some other sites, I came across these two simple examples: var obj = { "abc" : "hello" }; var x = "abc"; var y = obj[x]; console.log(y); //output - hello var user = { name: "John Doe", age: 30 }; var key = prompt("Enter the property to modify","name or age"); var value = prompt("Enter new value for " + key); user[key] = value; alert("New " + key + ": " + user[key]); The first example returns y to be undefined if in third line I replace the obj[x] with

What is a list of every unicode bracket-like characters (including, for example: {}[]()<> )? What is a good way to search for unicode characters? There is a plain-text database of information about every Unicode character available from the Unicode Consortium; the format is described in Unicode Annex #44 . The primary information is contained in UnicodeData.txt . Open and close punctuation characters are denoted with Ps (punctuation start) and Pe (punctuation end) in the General_Category field (the third field, delimited by ; ). Look for those character, and you'll find what you're looking for

Are square brackets in URLs allowed? I noticed that Apache commons HttpClient (3.0.1) throws an IOException, wget and Firefox however accept square brackets. URL example: http://example.com/path/to/file[3].html My HTTP client encounters such URLs but I'm not sure whether to patch the code or to throw an exception (as it actually should be). Justin Cormack RFC 3986 states A host identified by an Internet Protocol literal address, version 6 [RFC3513] or later, is distinguished by enclosing the IP literal within square brackets ("[" and "]"). This is the only place where square bracket characters

A dot . in a regular expression matches any single character. In order for regex to match a dot, the dot has to be escaped: \. It has been pointed out to me that inside square brackets [] a dot does not have to be escaped. For example, the expression: [.]{3} would match ... string. Doesn't it, really? And if so, is it true for all regex standards? lilactiger89 In a character class (square brackets) any character except ^ , - , ] or \ is a literal. This website is a brilliant reference and has lots of info on the nuances of different regex flavours. http://www.regular-expressions.info

I'm writing a PHP app and I want to make sure it will work with no errors. The original code: <?php $data = array('name' => 'test', 'id' => 'theID'); echo form_input($data); ?> Would the following work with no errors or is not recommended for some reason? <?= form_input(['name' => 'test', 'id' => 'theID']); ?> Are there any difference? I've looked again the data about array() and the short array method with square brackets [] in PHP.net but I'm not sure. And also, is the short php tag <?= ?> fine for echoing? Is there any version issue? (provided is enabled in php.ini) The Alpha Following []

There is this little trick question that some interviewers like to ask for whatever reason: int arr[] = {1, 2, 3}; 2[arr] = 5; // does this line compile? assert(arr[2] == 5); // does this assertion fail? From what I can understand, a[b] gets converted to *(a + b) and since addition is commutative it doesn't really matter their order, so 2[a] is really *(2 + a) and that works fine. Is this guaranteed to work by C and/or C++'s specs? Yes. 6.5.2.1 paragraph 1 (C99 standard) describes the arguments to the [] operator: One of the expressions shall have type "pointer to object type ", the other