string is an alias in C# for System.String. So technically, there is no difference. It’s like int vs. System.Int32. As far as guidelines, it’s generally recommended to use string any time you’re referring to an object. e.g. string place = “world”; Likewise, I think it’s generally recommended to use String if you need to refer … Read more
.gitignore will prevent untracked files from being added (without an add -f) to the set of files tracked by Git. However, Git will continue to track any files that are already being tracked. To stop tracking a file, we must remove it from the index: git rm –cached <file> To remove a folder and all … Read more
It’s a time zone change on December 31st in Shanghai. See this page for details of 1927 in Shanghai. Basically at midnight at the end of 1927, the clocks went back 5 minutes and 52 seconds. So “1927-12-31 23:54:08” actually happened twice, and it looks like Java is parsing it as the later possible instant … Read more
ECMAScript 6 introduced String.prototype.includes: const string = “foo”; const substring = “oo”; console.log(string.includes(substring)); // true includes doesn’t have Internet Explorer support, though. In ECMAScript 5 or older environments, use String.prototype.indexOf, which returns -1 when a substring cannot be found: var string = “foo”; var substring = “oo”; console.log(string.indexOf(substring) !== -1); // true
Yes, it was added in version 2.5. The expression syntax is: a if condition else b First condition is evaluated, then exactly one of either a or b is evaluated and returned based on the Boolean value of condition. If condition evaluates to True, then a is evaluated and returned but b is ignored, or … Read more
The difference is that functionOne is a function expression and so only defined when that line is reached, whereas functionTwo is a function declaration and is defined as soon as its surrounding function or script is executed (due to hoisting). For example, a function expression: // TypeError: functionOne is not a function functionOne(); var functionOne … Read more
The terms “pass-by-value” and “pass-by-reference” are have special, precisely defined meanings in computer science. These meanings differ from the intuition many people have when first hearing the terms. Much of the confusion in this discussion seems to come from this fact. The terms “pass-by-value” and “pass-by-reference” are talking about variables. Pass-by-value means that the value … Read more
This depends a lot on what you mean by “revert”. Temporarily switch to a different commit If you want to temporarily go back to it, fool around, then come back to where you are, all you have to do is check out the desired commit: # This will detach your HEAD, that is, leave you … Read more
A closure is a pairing of: A function and A reference to that function’s outer scope (lexical environment) A lexical environment is part of every execution context (stack frame) and is a map between identifiers (i.e. local variable names) and values. Every function in JavaScript maintains a reference to its outer lexical environment. This reference … Read more
Short Answer It’s boilerplate code that protects users from accidentally invoking the script when they didn’t intend to. Here are some common problems when the guard is omitted from a script: If you import the guardless script in another script (e.g. import my_script_without_a_name_eq_main_guard), then the latter script will trigger the former to run at import … Read more