[Rd] problem with eval(..., parent.frame(1L)) when package is not loaded

Ben Bolker bbolker at gmail.com
Fri Jun 28 20:55:14 CEST 2013


On 13-06-28 01:56 PM, Duncan Murdoch wrote:
> On 28/06/2013 12:42 PM, Ben Bolker wrote:
>> Duncan Murdoch <murdoch.duncan <at> gmail.com> writes:
>>
>> >
>>
>> [snip]
>> >
>> > The other choice is to use the explicit ::, i.e.
>> >
>> > mc[[1]] <- quote(lmer::lFormula)
>> >
>> > This would be the solution I'd prefer, but you seem to have some
>> > prejudice against :: .
>> >
>>
>>    I just thought that the whole point of using the machinery of
>> namespaces, environments, etc., was that we shouldn't need to
>> tell R explicitly what environment we were working in ...
> 
> And usually it works, just not always when you do surgery on
> expressions.  The snipped version worked, for instance.
> 
> Duncan Murdoch

  Fair enough.  I guess the problem is that I often look in core R
functions to figure out the right idioms to use, and it wasn't obvious
that this was a dangerous one ... it's fairly common and I don't see
warnings in the source code about it ...

  Ben



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