Macro fungi_lang::fgi_prop

macro_rules! fgi_prop {
    { fromast $ast:expr } => { ... };
    { ($($prop:tt)+) } => { ... };
    { tt } => { ... };
    { $p1:tt and $p2:tt and $($more:tt)+ } => { ... };
    { $p1:tt and $($p2:tt)+ } => { ... };
    { $i:tt % $j:tt : $($g:tt)+ } => { ... };
    { $i:tt = $j:tt : $($g:tt)+ } => { ... };
    { $($any:tt)* } => { ... };
}

Parser for Propositions

P ::=
    fromast ast     (inject ast nodes)
    (P)             (parens)
    tt              (truth)
    P and P and ... (extended conjunction)
    i % j : g       (index apartness)
    i = j : g       (index equivalence)