hackish writefln? and

[Frits van Bommel]

david wrote:
> Hello all!
> 
> Is
>     writefln( (i<10?" ":"") ~ "%d: %s", i, v);
> 
> supposed to work, according to the specs?
> Just looked at them, but couldn't quiet get it.

Yes, that should be fine (assuming i is some form of integer).

> But nevertheless it *does* work,
> no compile/runtime error and it acts
> also in the expected way.
> 
> BUT: I just came back from hunting (bugs),
> and you get an error if you write the above code
> in a file, read it in using std.file & std.stream,
> and writefln it back to the console:
> 
> *** bugtest.txt
> writefln( (i<10?" ":"") ~ "%d: %s", i, v);
> 
> *** bugtest.d
> import std.file, std.stream, std.stdio;
> void main()
> {
>     File file = new File;
>     file.open("bugtest.txt");
>     char[] line;
>     line = file.readLine();
>     file.close();
>     writefln(line);        // here we get an error
> }

That's a different matter entirely. String arguments to writef and 
friends are by default treated as format strings. Since the string you 
provide contains %d and %s, it expects two additional arguments. Since 
none are provided it throws an exception. Change the last line to
---
     writefln("%s", line);
---
to write out the exact contents of the string.

Stuff like this is why we *really* need non-formatting write functions :(...