R annoyances

From: Philippe Grosjean 

Hello,
Regarding use of parenthesis, it is true that R is much better with 
f(10) != f[10] != f[[10]], where Matlab is a little 
confusing. Also, in 
Matlab, you can use some functions without (), further adding to the 
confusion (the only example that comes to my mind in R is the 
use of '?' 
as shortcut for help()).

However, there is still a double use of () in R: it is both used for 
enclosing function arguments and for grouping operations. One 
language 
has a syntax that makes a totally unambiguous use of [], () and {} is 
Mathematica: [] is for subscript, {} is for function 
arguments and () is 
for grouping... but Mathematica code is really a pain to 
typeset and read.

So, all in all, I really like the S langage syntax: it is 
very readable 
and reasonably rigid...

Regarding T and F, I took the habit to *always* type them 
TRUE or FALSE. 
Again, very readable and not confusing at all. If T and F as 
equivalent 
to TRUE and FALSE would ever be deprecated and then defunct 
in further 
versions of R, well, I would not complain about it!

The only aspect I don't like is a too loosely use of the dot in 
functions: both in functions names, in object classes and in generic 
functions / methods. Hence, we have for instance: 'data.frame', 
'help.search' and 'summary.matrix'... just guess which one is 
an object 
class, which one is an ordinary function and which one is a S3 method 
(OK, S4 solves somehow the problem)? It would have been much 
better to 
*reserve* the use of a dot in a function name as a separator 
between the 
name of the generic function and the class to which it applies. Thus, 
'summary.matrix' would have been correct, but both 'data.frame' and 
'help.search' should have been spelled differently, perhaps 
'dataframe' 
and 'helpSearch'. Just a dream... because 'data.frame' will of course 
never be spelled differently!!!

Best,

Philippe Grosjean


Jan T. Kim wrote:

On Fri, May 20, 2005 at 08:14:24AM -0400, Liaw, Andy wrote:

From: Robin Hankin

On May 20, 2005, at 11:00 am, Jan T. Kim wrote:

On Thu, May 19, 2005 at 03:10:53PM -0400, John Fox wrote:

Since you can use variables named c, q, or t in any 

event, I don't 

see why
the existence of functions with these names is much of an 

impediment.

True, particularly since I'm not too likely to use these 

variables for 

(local)
functions, and variables of other types don't prevent 

functions from 

working.
(I thought this was a problem... I must be spoilt by 

recently having 

to read
too much Matlab code, where parentheses are used to both enclose 
subscripts and
parameter lists, thus rendering subscript expressions and 

function 

calls
syntactically indistinguishable.)

Heh, I'm a recovering Matlab  user too.  This is sooooooooooo true!

In Matlab:

f(10)    # function f() evaluated at 10
f(10)    # 10th element of vector f.  confusing!!

R uses round brackets in two unrelated ways:

 4*(1+2)  --- using "(" and ")" to signify grouping
f(8)  function f() evaluated at 8.

where there is no reason to use the same parenthesis 

symbol for both 

tasks.

The same is done in Fortran/C/C++/Java/Python and God knows how many
others...

And this is different from the subscripting / function call 

ambiguity,

as these languages (to the extent I know them) are designed 

such that

parentheses for precedence control are syntactically distinguishable
from those used for function parameter lists: If the 

opening parenthesis

is preceded by an identifier, that identifier is a function name and
the parenthesis opens a parameter list.

(Python is a somewhat messy case, though, because it uses 

parentheses

for tuples too.)

Best regards, Jan