calcfunction.coffee

calc = (tool,a1,a2,toolarg)->
	if tool is "relation"
		throw "Only one relation allowed!" if a2.type is "relation"
		type:"relation",objs:[a1,a2],val:toolarg
	else if a2.type is "relation"
		type: "relation",val:a2.val, objs:[calc(tool,a1,a2.objs[0]),a2.objs[1]]
	else if a2.isblock
		o tool,[a1,a2]
	else if tool in ["sum","product"] and tool is a2.type
		o tool, [a1].concat a2.objs
	else if not (tool is "sum" and a2.type is "product") and (a2.type in ["sum","product"] or (tool is "power" and a2.type is "fraction"))
		o a2.type, [calc(tool,a1,a2.objs[0])].concat a2.objs[1..]
	else 
		o tool,[a1,a2]