function fromBinaryString( bstr ) {
	var sign;
	var frac;
	var exp;

	if ( bstr.length !== 64 ) {
		throw new Error( format( 'invalid argument. Input string must have a length equal to %u. Value: `%s`.', 64, bstr ) );
	}
	// Sign bit:
	sign = ( bstr[0] === '1' ) ? -1.0 : 1.0;

	// Exponent bits:
	exp = parseInt( bstr.substring(1, 12), 2 ) - BIAS;

	// Fraction bits:
	frac = toDouble( bstr.substring( 12 ) );

	// Detect `0` (all 0s) and subnormals (exponent bits are all 0, but fraction bits are not all 0s)...
	if ( exp === -BIAS ) {
		if ( frac === 0.0 ) {
			return ( sign === 1.0 ) ? 0.0 : -0.0;
		}
		exp = -1022; // (1-BIAS); subnormals are special
	}
	// Detect `+-inf` (exponent bits are all 1 and fraction is 0) and `NaN` (exponent bits are all 1 and fraction is not 0)...
	else if ( exp === BIAS+1 ) {
		if ( frac === 0.0 ) {
			return ( sign === 1.0 ) ? PINF : NINF;
		}
		return NaN;
	}
	// Normal numbers...
	else {
		// Account for hidden/implicit bit (2^0):
		frac += 1.0;
	}
	return sign * frac * pow( 2.0, exp );
}
Creates a double-precision floating-point number from a literal bit representation.

@param {BinaryString} bstr - string which is a literal bit representation
@throws {Error} must provide a string with a length equal to `64`
@returns {number} double

@example
var bstr = '0100000000010000000000000000000000000000000000000000000000000000';
var val = fromBinaryString( bstr );
// returns 4.0

@example
var bstr = '0100000000001001001000011111101101010100010001000010110100011000';
var val = fromBinaryString( bstr );
// returns 3.141592653589793

@example
var bstr = '1111111111100001110011001111001110000101111010111100100010100000';
var val = fromBinaryString( bstr );
// returns -1.0e308

@example
var bstr = '1000000000000000000000000000000000000000000000000001100011010011';
var val = fromBinaryString( bstr );
// returns -3.14e-320

@example
var bstr = '0000000000000000000000000000000000000000000000000000000000000001';
var val = fromBinaryString( bstr );
// returns 5.0e-324

@example
var bstr = '0000000000000000000000000000000000000000000000000000000000000000';
var val = fromBinaryString( bstr );
// returns 0.0

@example
var bstr = '1000000000000000000000000000000000000000000000000000000000000000';
var val = fromBinaryString( bstr );
// returns -0.0

@example
var bstr = '0111111111111000000000000000000000000000000000000000000000000000';
var val = fromBinaryString( bstr );
// returns NaN

@example
var bstr = '0111111111110000000000000000000000000000000000000000000000000000';
var val = fromBinaryString( bstr );
// returns Infinity

@example
var bstr = '1111111111110000000000000000000000000000000000000000000000000000';
var val = fromBinaryString( bstr );
// returns -Infinity