playground.rs

#![allow(dead_code)]

macro_rules! pipe {
    ((); $e:expr; $($args:tt)*) => ($e);
    (($m:ident | $($ms:ident)|+) ; $($args:tt)*) => ($m!(($($ms)|+) ; $($args)*));
    (($m:ident) ; $($args:tt)*) => ($m!((); $($args)*));
    ($($ms:ident)|*) => (pipe!(($($ms)|*);));
}

macro_rules! incr {
    (($($ms:ident)|*) ; $($args:tt)*) => (pipe!(($($ms)|*) ; () $($args)*));
}

macro_rules! decr {
    (($($ms:ident)|*) ; () $($args:tt)*) => (pipe!(($($ms)|*) ; $($args)*));
}

macro_rules! zero {
    (($($ms:ident)|*) ; $($args:tt)*) => (pipe!(($($ms)|*) ; ; $($args)*));
}

macro_rules! one {
    (($($ms:ident)|*) ; $($args:tt)*) => (zero!((incr $(| $ms)*) ; $($args)*));
}

macro_rules! double {
    (($($ms:ident)|*) ; () $($n:tt)*) => (double!((incr | incr $(| $ms)*) ; $($n)*));
    (($($ms:ident)|*) ; ; $($rest:tt)*) => (zero!(($($ms)|*) ; $($rest)*));
}

macro_rules! thirty_one {
    (($($ms:ident)|*) ; $($args:tt)*) => (one!((double | double | double | double | double | decr $(| $ms)*) ; $($args)*));
}

macro_rules! count_rec {
    (($($ms:ident)|*) ; $n:expr ; () $($args:tt)*) => (count_rec!(($($ms)|*) ; $n + 1 ; $($args)*));
    (($($ms:ident)|*) ; $n:expr ; ; $($args:tt)*) => (pipe!(($($ms)|*) ; $n ; $($args)*));
}

macro_rules! count {
    (($($ms:ident)|*) ; $($args:tt)*) => (count_rec!(($($ms)|*) ; 0 ; $($args)*));
}

macro_rules! range_rec {
    (($($ms:ident)|*) ; $n:expr ; [$($ns:expr),*] ; () $($args:tt)*) => (range_rec!(($($ms)|*) ; $n + 1 ; [$($ns,)* $n] ; $($args)*));
    (($($ms:ident)|*) ; $n:expr ; [$($ns:expr),*] ; ; $($args:tt)*) => (pipe!(($($ms)|*) ; [$($ns),*] ; $($args)*));
}

macro_rules! range_decr {
    (($($ms:ident)|*) ; $n:expr ; []; () $($args:tt)*) => (pipe!(($($ms)|*) ; $n ; []; $($args)*));
}

macro_rules! range_lead {
    (($($ms:ident)|*) ; $n:expr ; () $($args:tt)*) => (range_lead!((range_decr $(| $ms)*) ; $n + 1 ; $($args)*));
    (($($ms:ident)|*) ; $n:expr ; ; $($args:tt)*) => (pipe!(($($ms)|*) ; $n ; [] ; $($args)*));
}

macro_rules! range {
    (($($ms:ident)|*) ; $($args:tt)*) => (range_lead!((range_rec $(| $ms)*) ; 0 ; $($args)*));
}

macro_rules! map_rule_repr {
    ($x: expr) => (95.52 / (8128.0 / ($x as f32) + 100.0));
}

macro_rules! map_rule {
    (($($ms:ident)|*) ; $($args:tt)*) => (pipe!(($($ms)|*) ; map_rule_repr ; $($args)*));
}

macro_rules! map {
    (($($ms:ident)|*) ; $f:ident ; [$($ns:expr),*] ; $($args:tt)*) => (pipe!(($($ms)|*) ; [$($f!($ns)),*] ; $($args)*));
}

fn main() {
    println!("{:?}", pipe!(one | incr | incr | incr | zero | range | map_rule | map));
}