R devel - Nov 2010 - Bug in parseNamespaceFile or switch( , ... ) ?

parseNamespaceFile() doesn't seem to detect misspelled directives. Looking 
at its code I see

 	switch(as.character(e[[1L]]),

 	<lots of args omitted here>,

 	stop(gettextf("unknown namespace directive: %s",
                 deparse(e)), call. = FALSE, domain = NA))

but this doesn't seem to function as I expect, viz. to stop with an error 
if I type a wrong directive.

Details:
> # create dummy NAMESPACE file with two bad / one good directives
> cat("blah( nada )\nblee( nil )\nexport( outDS
)\n",file="NAMESPACE")
> readLines("NAMESPACE")
[1] "blah( nada )"    "blee( nil )"     "export( outDS
)"
> parseNamespaceFile("",".") # now parse it
$imports
list()

$exports
[1] "outDS"

$exportPatterns
character(0)

$importClasses
list()

$importMethods
list()

$exportClasses
character(0)

$exportMethods
character(0)

$exportClassPatterns
character(0)

$dynlibs
character(0)

$nativeRoutines
list()

$S3methods
      [,1] [,2] [,3]
>
So, it picked up 'export' and ignored the other two lines.


Chuck

p.s.
> sessionInfo()
R version 2.12.0 (2010-10-15)
Platform: i386-apple-darwin9.8.0/i386 (32-bit)

locale:
[1] C

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods  
base
>




Charles C. Berry                            Dept of Family/Preventive Medicine
cberry at tajo.ucsd.edu			    UC San Diego
http://famprevmed.ucsd.edu/faculty/cberry/  La Jolla, San Diego 92093-0901

On 27/11/2010 5:58 PM, Charles C. Berry wrote:
>
> parseNamespaceFile() doesn't seem to detect misspelled directives.
Looking
> at its code I see
>
>   	switch(as.character(e[[1L]]),
>
>   	<lots of args omitted here>,
>
>   	stop(gettextf("unknown namespace directive: %s",
>                   deparse(e)), call. = FALSE, domain = NA))
>
> but this doesn't seem to function as I expect, viz. to stop with an
error
> if I type a wrong directive.
You're right, there was a typo in parseNamespaceFile.  (The typo was in 
this line:

                "=", "<-" = {

This should have been

                "=" =, "<-" = {

Without the extra = sign, the "=" was taken as the default value of
the
switch, and the stop() was never reached.

Conceivably switch() should complain if it is called with more than one 
default.

Duncan Murdoch
>
> Details:
>> # create dummy NAMESPACE file with two bad / one good directives
>> cat("blah( nada )\nblee( nil )\nexport( outDS
)\n",file="NAMESPACE")
>> readLines("NAMESPACE")
> [1] "blah( nada )"    "blee( nil )"     "export(
outDS )"
>> parseNamespaceFile("",".") # now parse it
> $imports
> list()
>
> $exports
> [1] "outDS"
>
> $exportPatterns
> character(0)
>
> $importClasses
> list()
>
> $importMethods
> list()
>
> $exportClasses
> character(0)
>
> $exportMethods
> character(0)
>
> $exportClassPatterns
> character(0)
>
> $dynlibs
> character(0)
>
> $nativeRoutines
> list()
>
> $S3methods
>        [,1] [,2] [,3]
>
>>
>
> So, it picked up 'export' and ignored the other two lines.
>
>
> Chuck
>
> p.s.
>
>> sessionInfo()
> R version 2.12.0 (2010-10-15)
> Platform: i386-apple-darwin9.8.0/i386 (32-bit)
>
> locale:
> [1] C
>
> attached base packages:
> [1] stats     graphics  grDevices utils     datasets  methods   base
>>
>
>
>
>
>
> Charles C. Berry                            Dept of Family/Preventive
Medicine
> cberry at tajo.ucsd.edu			    UC San Diego
> http://famprevmed.ucsd.edu/faculty/cberry/  La Jolla, San Diego 92093-0901
>
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> R-devel at r-project.org mailing list
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