command = "${" component "}"

cmdarg = "$" ~r"\d+\*?"


parenthised = ("(" component ")") / ("{" component "}")
true = "True" / "true"
false = "False" / "false"
bool = true / false

basicterm = bool / numeric / parenthised / quoted / cmdarg / var
term = ws* (function / basicterm) ws*

var = (parenthised / keyword) ("." keyword)*
function = var (ws+ basicterm)+

type = keyword
typecast = basicterm "::" type

test_eq = term "==" term
test_neq = term "!=" term
test_gt = term ">" term
test_geq = term ">=" term
test_lt = term "<" term
test_leq = term "<=" term
test = (test_eq/test_neq/test_gt/test_geq/test_lt/test_leq)

op_or = term ("||" term)+
op_and = term ("&&" term)+
op_add = term ("+" term)+
op_minus = term ("-" term)+
op_times = term ("*" term)+
op_exp = term ("**" term)+
op_divide = term ("/" term)+
op_div = term ("//" term)+
op_mod = term ("%" term)+
binop = (op_or/op_and/op_add/op_minus/op_times/op_exp/op_divide/op_div/op_mod)


cascade = term ("|" term)+

ternary = term "?" term ":" term
ifthenelse = "if" ws term ws "then" ws term (ws "elif" ws term ws "then" ws term)* (ws "else" ws term)? "fi"

equals = keyword ws* '=' ws* term
defines = keyword ws* ":=" ws* term
definesterm = keyword ws* "::=" ws* term

component = ws* (cascade / ternary / equals / defines / definesterm / binop / test / term) ws*


word = ~r"[_\w]+"
keyword = word
quoted = ~'"[^\"]*"'
numeric = ~r"[\d]+"
ws = ~r"\s+"