infinite recursion error for toJSON(fun)

Can you please stop with a more informative error? e.g. toJSON does not support converting R functions to JSON.

> toJSON(identity)
Error: evaluation nested too deeply: infinite recursion / options(expressions=)?
> toJSON(function(x) x)
Error: evaluation nested too deeply: infinite recursion / options(expressions=)?
> sessionInfo()
R version 3.0.2 (2013-09-25)
Platform: x86_64-unknown-linux-gnu (64-bit)

locale:
 [1] LC_CTYPE=en_CA.UTF-8       LC_NUMERIC=C              
 [3] LC_TIME=en_CA.UTF-8        LC_COLLATE=en_CA.UTF-8    
 [5] LC_MONETARY=en_CA.UTF-8    LC_MESSAGES=en_CA.UTF-8   
 [7] LC_PAPER=en_CA.UTF-8       LC_NAME=C                 
 [9] LC_ADDRESS=C               LC_TELEPHONE=C            
[11] LC_MEASUREMENT=en_CA.UTF-8 LC_IDENTIFICATION=C       

attached base packages:
[1] stats4    grid      graphics  utils     datasets  grDevices stats    
[8] methods   base     

other attached packages:
 [1] flexclust_1.3-4        modeltools_0.2-21      animint_2014.4.7      
 [4] scales_0.2.3           hexbin_1.26.3          MASS_7.3-29           
 [7] reshape2_1.2.2         maps_2.3-6             proto_0.3-10          
[10] directlabels_2014.1.31 quadprog_1.5-5         glmnet_1.9-5          
[13] Matrix_1.0-14          RColorBrewer_1.0-5     lattice_0.20-23       
[16] plotly_0.3.8           plyr_1.8.1             ggplot2_0.9.3.1       
[19] RJSONIO_1.0-3          RCurl_1.95-4.1         bitops_1.0-6          

loaded via a namespace (and not attached):
 [1] colorspace_1.2-4 compiler_3.0.2   dichromat_2.0-0  digest_0.6.4    
 [5] evaluate_0.5.1   formatR_0.10     gtable_0.1.2     knitr_1.5       
 [9] labeling_0.2     munsell_0.4.2    parallel_3.0.2   Rcpp_0.11.0     
[13] stringr_0.6.2    tools_3.0.2

duncantl / RJSONIO

infinite recursion error for toJSON(fun) #12