[R] Does R have a "const object"?

[Allan Kamau]

On Wed, Mar 16, 2011 at 6:47 AM, Thomas Lumley <tlumley at uw.edu> wrote:
> Actually, you can do this using locked bindings.  Look at ?lockBinding
>
> Locked bindings are how namespaces get const function definitions, and
> active bindings (on the same help page) are how R CMD check notices
> that you are using T and F when you mean TRUE and FALSE.
>
>   -thomas
>
>
> On Wed, Mar 16, 2011 at 1:52 PM,  <rex.dwyer at syngenta.com> wrote:
>> Cheer up! R is a step closer to that concept than the old FORTRAN compilers that couldn't even guarantee that 37 was a constant if used repeatedly in a subroutine call.
>>
>> -----Original Message-----
>> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On Behalf Of Uwe Ligges
>> Sent: Tuesday, March 15, 2011 2:23 PM
>> To: xiagao1982
>> Cc: r-help
>> Subject: Re: [R] Does R have a "const object"?
>>
>>
>>
>> On 15.03.2011 15:53, xiagao1982 wrote:
>>> Hi, all,
>>>
>>> Does R have a "const object" concept like which is in C++ language? I want to set some data frames as constant to avoid being modified unintentionally. Thanks!
>>
>>
>> Although there is almost never a "No" in R, the best short answer is: "No".
>>
>> Best,
>> Uwe  Ligges
>>
>>
>>>
>>>
>>>
>>> xiagao1982
>>> 2011-03-15
>>>
>>>       [[alternative HTML version deleted]]
>>>
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>>> and provide commented, minimal, self-contained, reproducible code.
>>
>> ______________________________________________
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>>
>>
>>
>>
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>
>
>
> --
> Thomas Lumley
> Professor of Biostatistics
> University of Auckland
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>

Perhaps a crude alternative is to place the value in some file perhaps
manually and set the file permissions to disallow writing but allow
reading. Then you can then always read the value from this file during
your programs execution.

Allan.