Function pom::parser::tag

source · 
pub fn tag<'a, 'b: 'a>(tag: &'b str) -> Parser<'a, char, &'a str>
Expand description

Success when tag matches current input.

Examples found in repository?
examples/json_char.rs (line 46)
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fn string<'a>() -> Parser<'a, char, String> {
	let special_char = sym('\\')
		| sym('/')
		| sym('"')
		| sym('b').map(|_| '\x08')
		| sym('f').map(|_| '\x0C')
		| sym('n').map(|_| '\n')
		| sym('r').map(|_| '\r')
		| sym('t').map(|_| '\t');
	let escape_sequence = sym('\\') * special_char;
	let char_string = (none_of("\\\"") | escape_sequence)
		.repeat(1..)
		.map(String::from_iter);
	let utf16_char = tag("\\u")
		* is_a(|c: char| c.is_digit(16))
			.repeat(4)
			.map(String::from_iter)
			.convert(|digits| u16::from_str_radix(&digits, 16));
	let utf16_string = utf16_char.repeat(1..).map(|chars| {
		decode_utf16(chars)
			.map(|r| r.unwrap_or(REPLACEMENT_CHARACTER))
			.collect::<String>()
	});
	let string = sym('"') * (char_string | utf16_string).repeat(0..) - sym('"');
	string.map(|strings| strings.concat())
}

fn array<'a>() -> Parser<'a, char, Vec<JsonValue>> {
	let elems = list(call(value), sym(',') * space());
	sym('[') * space() * elems - sym(']')
}

fn object<'a>() -> Parser<'a, char, HashMap<String, JsonValue>> {
	let member = string() - space() - sym(':') - space() + call(value);
	let members = list(member, sym(',') * space());
	let obj = sym('{') * space() * members - sym('}');
	obj.map(|members| members.into_iter().collect::<HashMap<_, _>>())
}

fn value<'a>() -> Parser<'a, char, JsonValue> {
	(tag("null").map(|_| JsonValue::Null)
		| tag("true").map(|_| JsonValue::Bool(true))
		| tag("false").map(|_| JsonValue::Bool(false))
		| number().map(|num| JsonValue::Num(num))
		| string().map(|text| JsonValue::Str(text))
		| array().map(|arr| JsonValue::Array(arr))
		| object().map(|obj| JsonValue::Object(obj)))
		- space()
}