[R] Last expression entered by user

[Daniel Haase]

Hi,

I am looking for a way to find out the last expression that was  
entered by the user, similar to ".Last.value", but for the unevaluated  
expression instead of the evaluated one.

Example:
> x <- 4
> x*x + 3
[1] 19
> .Last.value # that's the evaluated last expression
[1] 19
# but I am looking for the unevaluated expression (".Last.expression",  
so to say), which would be expression(x * x + 3) in this case

Daniel