An lvalue is a value that can be assigned to: lvalue = rvalue; It’s short for “left value” or “lefthand value” and it’s basically just the value on the left of the = sign, i.e. the value you assign something to. As an example of what is not an lvalue (i.e rvalue only): printf(“Hello, world!\n”) … Read more
The best paper I ever read on compilers is dated 1964 “META II a syntax-oriented compiler writing language” by Val Schorre. (http://doi.acm.org/10.1145/800257.808896) In 10 pages, he shows you how to build an astoundingly simple but very effective compiler-compiler, provides you with with the compiler-compiler grammar and provides you with enough details for you to hand … Read more
There’s a simple ad hoc proof for this. Since you can build a Turing complete language using strictly iterative structures and a Turing complete language using only recursive structures, then the two are therefore equivalent.
The most obvious problem is with function overriding. Let’s say have two classes A and B, both of which define a method doSomething. Now you define a third class C, which inherits from both A and B, but you don’t override the doSomething method. When the compiler seed this code… C c = new C(); … Read more
Pattern Recursion With recursive patterns, you have a form of recursive descent matching. This is fine for a variety of problems, but once you want to actually do recursive descent parsing, you need to insert capture groups here and there, and it is awkward to recover the full parse structure in this way. Damian Conway’s … Read more