#importonce					// <-- This is a library, we only want it included once
.filenamespace MyFunctions	// <-- Sets up a 'MyFunctions' namespace for this file

//-----------------------------
// Help functions 
//-----------------------------

.function failOnOverflow(x, limit) { //<-- This function can only be seen within the MyFunctions namespace
	.if (x>=limit)
		.error("value too high: " + x) 

	.if (x<0)
		.error("value too low:x " + x) 
}

//-----------------------------
// Library functions 
//-----------------------------
.function @toSpritePtr(addr) { 		// <-- @ puts this function in the root scope so everyone can see it
	.eval failOnOverflow(addr,$10000)
	.return (addr&$3fff)/$40
}