if(valueExpr.isBoolean) _.errout('test: ' + valueExpr.isBoolean)
function booleanF(bindings){
		var value = valueExpr(bindings)
		value = !!value
		//if(rel.params[1].params[0].value === true && rel.params[1].params[1].was && rel.params[1].params[1].was.view === 'list') console.log('switch value: ' + value)//+ ' ' + JSON.stringify(rel.params[2]))//.params[0].view)
		for(var i=0;i<caseValues.length;++i){
			var cv = caseValues[i]
			if(cv === value){
				var res = caseExprs[i](bindings)
				//if(rel.params[1].params[0].value === true && rel.params[1].params[1].was && rel.params[1].params[1].was.view === 'list') console.log('case result: ' + value + ' -> ' + JSON.stringify(res))
				return res
			}
		}
		if(defaultExpr){
			var res = defaultExpr(bindings)
			//if(rel.params[1].params[0].value === true && rel.params[1].params[1].was && rel.params[1].params[1].was.view === 'list') console.log('default result: ' + value + ' -> ' + JSON.stringify(res))
			return res
		}else{
			console.log('WARNING: no case matched and no default case provided')
		}
	}