@LuisMendo Exactly. I think "apply X to range Y" is common enough in code golf that it warrants some special consideration. One day I might get around to seeing how the MATL compiler works and suggest the actual implementation myself, but I've been saying that for a year now...

"Apply function X to range or array Y" cannot be done for a general function. MATL doesn't have a concept of a callable function. Take for example XQ (accumarray). In MATLAB you can use accumarray(..., f) for any function (handle) f. But in MATL XQ takes a number which specifies a predefined set of allowed functions.

Similarly, there are cummax and cumsum, but not a way to have an arbitrary function be applied cumulatively.

Introducing that sort of thing would be a big change to the language, not just the compiler.

I know, which is why I think a shorthand for "call ( using the indices and data from the last call of )" might be a good solution.

That means basically one extra magical clipboard similar to M

(it could even be M if the argument order for ( was different)