Your list is missing "Rich Value Types" (like stocks or geographical locations). Those can be stored in a cell, and then have other cells access their fields wi

Your list is missing "Rich Value Types" (like stocks or geographical locations). Those can be stored in a cell, and then have other cells access their fields with =FIELDVALUE(...). Indeed the complete list of cell data in the api is: boolean, double, empty, error, integer, richValue, string, unknown Further not every valid excel value (in the sense that you can pass it as a function argument) can be a cell value. For example arrays. Arrays need to spill into multiple cells if they are a result. Similarly, to my knowledge cell references cannot be the result value of a cell, as they would get dereferenced to get their underlying value as part of evaluation. On the other hand they most certainly are something that can be passed to a function without getting dereferenced first. The name manager allows naming certain values that cannot be a cell result (like arrays), which makes it seem more likely that lambdas are full fledged data types, that could be passed to other lambdas. If I had access to a beta copy of excel, it would be easy to find out by running: =LET(doubleapply, LAMBDA(x, y, x(x(y))), plusthree, LAMBDA(x, x+3), doubleapply(plusthree,5)) If that works, great lambdas are clearly a new first class data type. If it does not work, then obviously they are some form of second class citizen.