[Rd] codetools::checkUsage should ignore expression in Quote(expr) (PR#10719)

[bill at insightful.com]

Full_Name: Bill Dunlap
Version: R version 2.7.0 Under development (unstable) (2008-02-05 r44340)
OS: Linux
Submission from: (NULL) (76.28.245.14)


codetools::checkUsage() should treat the Quote() function
just as it does the quote() and expression() functions: by
ignoring its argument.  Currently 'R CMD check pkg' complains
if pkg's R code calls Quote(unknownName) but is quiet about
quote(unknownName).  quote() and Quote() are identical, but
Quote is provided for compatibility with Splus (and version
4 of S).

I would expect all the following to make no complaints.

> codetools::checkUsage(function(x=Quote(hello(world)))x)
<anonymous>: no visible global function definition for 'hello'
<anonymous>: no visible binding for global variable 'world'
> codetools::checkUsage(function(x=quote(hello(world)))x)
> codetools::checkUsage(function(x=expression(hello(world)))x)