const constant = s=> map(some(({value, type})=> value === s && type === "NAME"), tokval);
const op = s=> map(some(({value, type})=> value === s && type === "OP"), tokval);
export function getParser() {
let name = map(some(t('NAME')), tokval);
let rawString = map(some(t('STRING')), tokval, strip);
let num = map(some(t("NUMBER")), tokval, parseFloat);
let _true = map(constant("true"), always(true));
let _false = map(constant("false"), always(false));
let _null = map(constant("null"), always(null));
let enumItem = or(num, _true, _false, _null, name, rawString);
let _enum = anno("enum", sep(skip(op("|")), enumItem));
let boolean = anno("boolean", map(constant("bool"), always(null)));
let null_ = anno("null", map(constant("null"), always(null)));
let numRange = seq(skip(op('{')),
maybe(num), skip(op(",")), maybe(num),
skip(op('}')));
let regexp = map(some(t("REGEXP")), tokval, strip);
let string = anno("string", or(seq(skip(constant("str")), maybe(numRange), maybe(regexp)),
seq(maybe(numRange), regexp)));
let format = anno("format", seq(skip(op("%")), name));
let numRangeStep = seq(skip(op("{")),
maybe(num), skip(op(",")), maybe(num),
maybe(seq(skip(op(",")), num)),
skip(op('}')));
let number = anno("number", seq(skip(constant("num")), maybe(numRangeStep)));
let integer = anno("integer", seq(skip(constant("int")), maybe(numRangeStep)));
let schema = decl();
let array = anno("array", seq(skip(op("[")),
maybe(sep(skip(op(",")), schema)),
skip(op("]")),
maybe(numRange),
maybe(op("!"))));
let _indent = anno("indent", map(some(t("INDENT")), tokval));
let _dedent = some(t("DEDENT"), tokval);
let nl = some(t("NL"));
let definition = seq(op("@"), name);
let key = seq(or(seq(or(name, string), maybe(op("?"))),
definition),
skip(op(":")));
let ref = anno("ref", seq(skip(op("@")), or(name,
seq(name, skip(op(":")), name))));
let refDeclaration = map(seq(skip(op("@")), name, rawString),
([name, url])=> [name, "extref", url]);
let baseSchema = or(ref, string, number, integer, boolean, null_, format, array);
let oneof = anno("oneof", map(seq(oneplus(seq(baseSchema, skip(op("|")))),
baseSchema), append));
let allof = anno("allof", map(seq(oneplus(seq(baseSchema, skip(op("&")))),
baseSchema), append));
let anyof = anno("anyof", map(seq(oneplus(seq(baseSchema, skip(op("/")))),
baseSchema), append));
let simpleSchema = or(anyof, oneof, allof, baseSchema, _enum);
let dots = map(op("..."), always([null, "open", null]));
let refid = map(seq(skip(op("@")), rawString), x=> [null, "id", x]);
let object = decl();
let nestedObject = seq(skip(nl), skip(_indent), object, skip(_dedent));
object.define(anno("object",
map(oneplus(or(map(seq(key,
or(seq(simpleSchema, skip(nl)),
nestedObject)), append),
seq(or(dots, refid, refDeclaration), skip(nl)))),
list2dict)));
schema.define(or(object, simpleSchema));
return seq(skip(maybe(nl)), schema, skip(maybe(nl)), skip(done));
}