digitalmars.D.learn - compile time printf -> .NET style format string conversion template.
- Neal Alexander (29/29) Jan 03 2008 Alright the basic idea behind this was:
- Neal Alexander (7/45) Jan 03 2008 figured out one of the questions at least haha:
- Matti Niemenmaa (11/11) Jan 04 2008 Neal Alexander wrote:
Alright the basic idea behind this was: - During tango porting i want all the stdlib wrapping done in 1 module. - Any function that takes a format string cant be wrapped transparently without converting the string or doing something half baked (right?). So i wrote this compile-time conversion template: http://paste.dprogramming.com/dpjq2ug6 (See the FMT template for discussion purposes. The rest is just conversion/parsing). Now for the questions: - Why cant i do return x ~ FMT!(s[i .. $]); at line 106? This would avoid having to call skip() to count the fmt string length a 2nd time. The compiler complains s[i .. $] is an invalid argument or somethig. - How do i template the print function so that the compiler retains the immediateness of the format string arg. with something like this you'd have to do: --------------------------- void print(T...)(T t) { version (Tango) Stdout.formatln(t); else writefln(t); } print(FMT!("whatever %d"), 0); where ideally you would want something like this: --------------------------- void print(T...)(char[] fmt, T t) { version (Tango) Stdout.formatln(FMT!(fmt), t); else writefln(fmt, t); } print("whatever %d", 0);
Jan 03 2008
Neal Alexander wrote:Alright the basic idea behind this was: - During tango porting i want all the stdlib wrapping done in 1 module. - Any function that takes a format string cant be wrapped transparently without converting the string or doing something half baked (right?). So i wrote this compile-time conversion template: http://paste.dprogramming.com/dpjq2ug6 (See the FMT template for discussion purposes. The rest is just conversion/parsing). Now for the questions: - Why cant i do return x ~ FMT!(s[i .. $]); at line 106? This would avoid having to call skip() to count the fmt string length a 2nd time. The compiler complains s[i .. $] is an invalid argument or somethig. - How do i template the print function so that the compiler retains the immediateness of the format string arg. with something like this you'd have to do: --------------------------- void print(T...)(T t) { version (Tango) Stdout.formatln(t); else writefln(t); } print(FMT!("whatever %d"), 0); where ideally you would want something like this: --------------------------- void print(T...)(char[] fmt, T t) { version (Tango) Stdout.formatln(FMT!(fmt), t); else writefln(fmt, t); } print("whatever %d", 0);figured out one of the questions at least haha: template print(char[] fmt, T...) { void print(){ Stdout.formatln(FMT!(fmt), T); } } print!(...);
Jan 03 2008
Neal Alexander wrote: In case you're interested, attached is my (command-line tool) attempt at doing the same thing: converting writef's formatting strings to Tango's. I soon gave up as doing a character-by-character exact conversion leads to too many special cases. It's a couple months old and thus probably doesn't even compile with the current Tango. On top of that, the code is fairly ugly as I didn't expect it to blow up to such a length. But if you want to support everything writef parses (what I tried) there might be something of use in there. -- E-mail address: matti.niemenmaa+news, domain is iki (DOT) fi
Jan 04 2008