#keywords hard strict: fun let mut not and or;
unop = '-' | '~' | "not";
binop = '+' | '-' | '*' | '/' | '%' | '|' | '^' | '&' | '>>' | '<<';
logicop = "and" | "or";
name = @ident | '@' "name" (expr);
tuple = (expr ','*~);
reshape = '.' name;
chainop = reshape | tuple;
term = <leaf | unop term> chainop .*~;
binexpr = term binop+;
expr = binexpr logicop+;
param = name ':' expr;
param_inferrable = name <':' expr>?;
function_def = "fun" name <':' [param_inferrable ','*~]>? (param ','*~)? <'->' expr>? <'=' expr | block>;