+ return new FlatString.full(ns, elen, 0, elen)
+ end
+
+ # Return self as a C hexadecimal digest where bytes are prefixed by `\x`
+ #
+ # The output is compatible with literal stream of bytes for most languages
+ # including C and Nit.
+ #
+ # ~~~
+ # var b = "abcd".to_bytes
+ # assert b.chexdigest == "\\x61\\x62\\x63\\x64"
+ # assert b.chexdigest.unescape_to_bytes == b
+ # ~~~
+ fun chexdigest: String do
+ var elen = length * 4
+ var ns = new CString(elen)
+ var i = 0
+ var oi = 0
+ while i < length do
+ ns[oi] = u'\\'
+ ns[oi+1] = u'x'
+ self[i].add_digest_at(ns, oi+2)
+ i += 1
+ oi += 4
+ end
+ return new FlatString.full(ns, elen, 0, elen)
+ end
+
+
+ # Returns self as a stream of bits (0 and 1)
+ #
+ # ~~~
+ # var b = "abcd".to_bytes
+ # assert b.binarydigest == "01100001011000100110001101100100"
+ # assert b.binarydigest.binarydigest_to_bytes == b
+ # ~~~
+ fun binarydigest: String do
+ var elen = length * 8
+ var ns = new CString(elen)
+ var i = 0
+ var oi = 0
+ while i < length do
+ var c = self[i]
+ var b = 128
+ while b > 0 do
+ if c & b == 0 then
+ ns[oi] = u'0'
+ else
+ ns[oi] = u'1'
+ end
+ oi += 1
+ b = b >> 1
+ end
+ i += 1
+ end
+ return new FlatString.full(ns, elen, 0, elen)
+ end
+
+ # Interprets `self` as a big-endian integer (unsigned by default)
+ #
+ # ~~~
+ # var b = "0102".hexdigest_to_bytes
+ # assert b.to_i == 258
+ #
+ # assert "01".hexdigest_to_bytes.to_i == 1
+ # assert "FF".hexdigest_to_bytes.to_i == 255
+ # assert "0000".hexdigest_to_bytes.to_i == 0
+ # ~~~
+ #
+ # If `self.is_empty`, 0 is returned.
+ #
+ # ~~~
+ # assert "".hexdigest_to_bytes.to_i == 0
+ # ~~~
+ #
+ # If `signed == true`, the bytes are read as a signed integer.
+ # As usual, the sign bit is the left most bit, no matter the
+ # `length` of `self`.
+ #
+ # ~~~
+ # assert "01".hexdigest_to_bytes.to_i(true) == 1
+ # assert "FF".hexdigest_to_bytes.to_i(true) == -1
+ # assert "00FF".hexdigest_to_bytes.to_i(true) == 255
+ # assert "E0".hexdigest_to_bytes.to_i(true) == -32
+ # assert "FE00".hexdigest_to_bytes.to_i(true) == -512
+ # assert "FEFEFE".hexdigest_to_bytes.to_i(true) == -65794
+ # ~~~
+ #
+ # `Int::to_bytes` is a loosely reverse method.
+ #
+ # ~~~
+ # assert b.to_i.to_bytes == b
+ # assert (b.to_i + 1).to_bytes.hexdigest == "0103"
+ # assert "0001".hexdigest_to_bytes.to_i.to_bytes.hexdigest == "01"
+ #
+ # assert (-32).to_bytes.to_i(true) == -32
+ # ~~~
+ #
+ # Warning: `Int` might overflow for bytes with more than 60 bits.
+ fun to_i(signed: nullable Bool): Int do
+ var res = 0
+ var i = 0
+ while i < length do
+ res *= 256
+ res += self[i].to_i
+ i += 1
+ end
+
+ # Two's complement is `signed`
+ if signed == true and not_empty and first > 0x80 then
+ var ff = 0
+ for j in [0..length[ do
+ ff *= 0x100
+ ff += 0xFF
+ end
+
+ res = -((res ^ ff) + 1)
+ end
+
+ return res