[Rd] expression objects

Parlamis Franklin fparlamis at mac.com
Tue May 2 07:16:06 CEST 2006


if 'e' is a vector of mode 'expression', will the following always  
return TRUE:

identical(e, parse(text = as.character(e)))  ?

 > (e <- expression(x, y, z, 200*f%/%d, sin(e)))
expression(x, y, z, 200 * f%/%d, sin(e))
 > identical(e, parse(text = as.character(e)))
[1] TRUE

i have been relying on this fact in some of my code, and would be  
appreciative of any counterexamples.

franklin parlamis



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