solid

text   <- string:blob (liquid:liquid text:text)? `{text, Node}`;
blob   <- ((!open_block .)*) ~;
liquid <- open_block:open_block space (argument:argument filters:filters / argument:argument)? space close_block:close_block `
case Node of
  [_, _, Block, _, _] -> lists:flatten([Block])
end
`;
filters <- (space "|" space filter (":" space arguments)? )+`
[case N of
  [_, _, _, Filter, [_, _, Args]] -> {Filter, Args};
  [_, _, _, Filter, _] -> {Filter, []}
end || N <- Node]
`;
arguments <- argument (space "," space argument)* `
case Node of
  [Arg1, Args] -> [Arg1 | [Arg || [_, _, _, Arg] <- Args]]
end
`;
argument <- value:value / field:field ~;
value <- space (string / number / true / false / null) space `lists:nth(2, Node)`;

%% Terminals

open_block     <- "{{" ~;
close_block    <- "}}" ~;
field          <- [0-9a-zA-Z\.]* `iolist_to_binary(Node)`;
filter         <- [a-zA-Z]* `iolist_to_binary(Node)`;
space          <- [ \t\n\s\r]* `{space, iolist_to_binary(Node)}`;

string <- '"' chars:(!'"' ("\\\\" / '\\"' / .))* '"' `
iolist_to_binary(proplists:get_value(chars, Node))
`;
number <- int frac? exp?
`
case Node of
  [Int, [], []] -> list_to_integer(binary_to_list(iolist_to_binary(Int)));
  [Int, Frac, []] -> list_to_float(binary_to_list(iolist_to_binary([Int, Frac])));
  [Int, [], Exp] -> list_to_float(binary_to_list(iolist_to_binary([Int, ".0", Exp])));
  _ -> list_to_float(binary_to_list(iolist_to_binary(Node)))
end
`;
int <- '-'? (non_zero_digit digit+) / digit ~;
frac <- '.' digit+ ~;
exp <- e digit+ ~;
e <- [eE] ('+' / '-')? ~;
non_zero_digit <- [1-9] ~;
digit <- [0-9] ~;
true <- 'true' `true`;
false <- 'false' `false`;
null <- 'nil' `nil`;