scan_fmt

scan_fmt provides a simple scanf()-like input for Rust. The goal is to make it easier to read data from a string or stdin.

Currently the format string supports the following special sequences:

Examples

 #[macro_use] extern crate scan_fmt;
 use std::error::Error ;
 fn main() -> Result<(),Box<dyn Error>> {
   let (a,b,c) = scan_fmt!( "hello 0x12 345 bye",  // input string
                            "hello {x} {} {}",     // format
                            [hex u8], i32, String) ? ;   // type of a-c Options
   assert_eq!( a, 0x12 ) ;
   assert_eq!( b, 345 ) ;
   assert_eq!( c, "bye" ) ;

   println!("Enter something like: 123-22");
   let (c,d) = scanln_fmt!( "{d}-{d}", // format
                            u16, u8) ? ;  // type of a&b Options
   println!("Got {} and {}",c,d) ;
   // Note - currently scanln_fmt! just calls unwrap() on read_line()

   let (a,b) = scan_fmt_some!( "hello 12 345", // input string
                               "hello {} {}",   // format
                               u8, i32) ;   // types
   assert_eq!( a, Some(12) ) ;
   assert_eq!( b, Some(345) ) ;
   Ok(())
  }

Limitations

There is no compile-time warning if the number of {}'s in the format string doesn't match the number of return values. You'll just get None for extra return values. See src/lib.rs for more details.