Bitmask convenience functions in JavaScript.

gistfile1.js

// Return the value of one offset bit in mask
function bit_query( mask, bit ) {
	return ( ( mask & ( 1 << bit ) ) >> bit );
}

// Return input mask with offset bit switched ON
function bit_on( mask, bit ) {
	return ( mask | ( 1 << bit ) );
}

// Return input mask with offset bit switched OFF
function bit_off( mask, bit ) {
	return ( mask & ~( 1 << bit ) );
}

// Return input mask with offset bit TOGGLED 
function bit_toggle( mask, bit ) {
	return ( mask ^ ( 1 << bit ) );
}

// Return decimal input in binary form
function dec2bin( dec ) {
	for ( var out = new String; dec; dec >>= 1 )
		out = new String( dec & 1 ).concat( out );
	return out;	
}