[R] difference between <- and =
Richard A. O'Keefe
ok at cs.otago.ac.nz
Mon Sep 1 04:49:00 CEST 2003
Levi Larkey <larkey at mail.utexas.edu> wrote:
a perfect illustration of why allowing "=" as an alternative
spelling for "<-" was always an obviously really bad idea.
Is there any reason for using one operator over the other outside of
function definitions and calls?
You should never use "=" for assignment unless you are suffering such
severe "C" withdrawal symptoms that the doctor just had to give you a
shot to calm you down. It is best to keep different symbols for
different purposes. (I note that Ada uses ":=" for assignment and
"=>" for keyword arguments.)
Something that would be quite useful would be an option asking R to
warn you
- if you have any assignment operator in a function argument
(thanks to lazy evaluation this probably *won't* do what you
expect)
- if you have "=" anywhere except for binding a name to an argument.
Perhaps these could be two options.
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