Function as argument for all functions that set properties?

Function as argument for all functions that set properties?


I've just started to look over jQuery for some projects I'm planning.
I noticed that the attr() function can accept a function as it's
second argument to generate the value to be set. However, none of the
other functions that set text/attributes (e.g., text, val, add, etc.)
can do the same. Wouldn't it be more consistent (not to mention
totally cool) to give every function that sets attributes/text the
ability to generate the value using a function? Why is attr() so
special?