String interpolation macros for rust
This crate uses procmacrohack, so it works with stable version of rustc.
Macros provided by this crate correspond to std's formatting macros (format,print, println, eprint, eprintln, ...).
You can use these macros just same as std's ones.
```rust use interpol::println;
let a = 3; let b = 4; println!("{a} times {b} is {a * b}."); // => "3 times 4 is 12." ```
It is also able to specify formatting option:
```rust let pi = 3.14; println!("{pi:.10}"); // => "3.1400000000" println!("{123:x}"); // => "7b"
let v = vec![1, 2, 3]; println!("{v:?}"); // => "[1, 2, 3]" ```
Correctly handles unicode characters:
rust
let world = "世界";
println!("ハロー {world}"); // => "ハロー 世界"
It is able to write expressions:
```rust println!("PI = {std::f64::consts::PI:.10}"); // => "PI = 3.1415926536"
println!("PI = { 1.0_f64.atan() * 4.0 :.10}"); // => "PI = 3.1415926536" ```
You can also write nested block expressions:
```rust println!("{ { let t = 123; t * t } }"); // => "15129"
println!("{{ let t = 123; t * t }}"); // "{{" and "}}" is escaped so the result is: // => "{ let t = 123; t * t }"
```