[R] what's going on here with substitute() ?

[Peter Dalgaard]

Tony Plate <tplate at blackmesacapital.com> writes:

> Why is the body of the function "X" when I substituted a different
> expression for X? Also, given that the body of the function is X, how
> does the function evaluate to TRUE since X is not defined anywhere
> (except in a list that should have been discarded.)
> 
> This happens with both R 1.7.1 and R 1.8.0 (under Windows 2000).
> 
> (yes, I did discover the function is.R(), but I still want to discover
> what's going here.)

I think you are defeating the keep.source mechanism. What you're
seeing is not the actual function but its source attribute. Try
attributes(this.is.R) <- NULL and see what happens.

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
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