Programming in D for Ruby Programmers

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This page is under community development.

In the meantime, you may find the following links of interest as a Ruby programmer:

Adding methods to existing classes / UFCS

In Ruby, it's possible to add methods to existing classes, even builtin ones:

class String
    def underline
        puts self
        puts "=" * self.length
    end
end

"Hello, world!".underline

# prints:
# Hello, world!
# =============

Because it uses a static compilation model, it's not possible to do exactly the same in D. However, D allows calling a free function as if it were a method, which mostly has the same effect from a caller's point of view, and has the additional advantage of not polluting the type's namespace:

void underline(string s) {
    import std.stdio : writeln;
    import std.range : repeat;
    writeln(s);
    writeln('='.repeat(s.length));
}
 
void main() {
    "Hello, world!".underline();
}