`std.bigint.big_int.this` - multiple declarations

Function BigInt.this

Construct a BigInt from a decimal or hexadecimal string.

The number must be in the form of a D decimal or hex literal:

It may have a leading + or - sign; followed by "0x" if hexadecimal.

Underscores are permitted.

this(T)(
  T s
);

Should throw a IllegalArgumentException/ConvError if invalid character found

Construct a BigInt from another BigInt.

this(T)(
  T x
) pure
if (is(Unqual!T == BigInt));

const(BigInt) b1 = BigInt("1_234_567_890");
BigInt b2 = BigInt(b1);
assert(b2 == BigInt("1_234_567_890"));

Construct a BigInt from a built-in integral type.

this(T)(
  T x
) pure
if (isIntegral!T);

ulong data = 1_000_000_000_000;
auto bigData = BigInt(data);
assert(data == BigInt("1_000_000_000_000"));