?: is a form of the conditional operator which was previously available only as: expr ? val_if_true : val_if_false In 5.3 it’s possible to leave out the middle part, e.g. expr ?: val_if_false which is equivalent to: expr ? expr : val_if_false From the manual: Since PHP 5.3, it is possible to leave out the … Read more
Microsoft proposes Rolsyn API as an implementation of C# compiler with public API. It contains individual APIs for each of compiler pipeline stages: syntax analysis, symbol creation, binding, MSIL emission. You can provide your own implementation of syntax parser or extend existing one in order to get C# compiler w/ any features you would like. … Read more
It evaluates to the left operand if the left operand is truthy, and the right operand otherwise. In pseudocode, foo = bar ?: baz; roughly resolves to foo = bar ? bar : baz; or if (bar) { foo = bar; } else { foo = baz; } with the difference that bar will only … Read more
(This is longer than I intended; please bear with me.) Most languages are made up of something called a “syntax”: the language is comprised of several well-defined keywords, and the complete range of expressions that you can construct in that language is built up from that syntax. For example, let’s say you have a simple … Read more