Question

I’m trying to write generic code that can lex any stream of characters (dchars) into anywhere… whether it’s from a file or from stdin into another file or stdout.

How do I do this?

It seems like stdin and stdout are painful to use with InputRange and OutputRange (since I have to wrap them manuallly every time), and I can’t use std.stdio.Stream because it gives me bytes, not strings… and I can’t find any adapter to convert from one into the other easily.

So effectively, I can’t find a good way to use stdin/stdout in my programs.

Is there something e.g. like .NET’s TextReader that can abstractly read text as an InputRange!dchar regardless of whether its input is a string, the console, or a file?

Answer 1

The proper function which takes a dchar input range is:

void func(Range)(Range input)
    if(isInputRange!Range && is(ElementType!Range == dchar))
{}

However, you must have an input range that gets its input from stdin. There is talk of needing to rework stdio/streaming which has not been done yet. There is an undocumented range of dchar for stdin.