Scarica un pacchetto e tutte le dipendenze

Question

Sto provando a scaricare un pacchetto con tutte le sue dipendenze. Il problema che sto incontrando è l'ordine in cui scaricare le dipendenze. Poiché le dipendenze sono ricorsive, possono essere scaricate solo dal basso verso l'alto nell'albero delle dipendenze.

Esiste un modo facile o nativo in R per ottenere ciò? Qui di seguito una prima andare in quello che vorrei realizzare:

eval_current <- function(expr, envir=parent.frame(), timeout=60){ 
    #set the timeout 
    setTimeLimit(elapsed=timeout, transient=TRUE); 

    #currently loaded packages 
    currentlyattached <- search(); 
    currentlyloaded <- loadedNamespaces(); 

    on.exit({ 
    #reset time limit 
    setTimeLimit(cpu=Inf, elapsed=Inf, transient=FALSE); 

    #try to detach packages that were attached during eval 
    nowattached <- search(); 
    todetach <- nowattached[!(nowattached %in% currentlyattached)]; 
    for(i in seq_along(todetach)){ 
     try(detach(todetach[i], unload=TRUE, character.only=TRUE, force=TRUE)); 
    } 

    #try to unload packages that are still loaded 
    nowloaded <- loadedNamespaces(); 
    tounload <- nowloaded[!(nowloaded %in% currentlyloaded)]; 
    for(i in seq_along(tounload)){ 
     try(unloadNamespace(tounload[i])); 
    }  

    }); 

    eval(expr, envir) 
} 

Ma si traduce in:

> eval_current({library(ggplot2); qplot(rnorm(100));}) 
Error in unloadNamespace(tounload[i]) : 
    namespace ‘colorspace’ is imported by ‘munsell’ so cannot be unloaded 
Error in unloadNamespace(tounload[i]) : 
    namespace ‘dichromat’ is imported by ‘scales’ so cannot be unloaded 
Error in unloadNamespace(tounload[i]) : 
    namespace ‘grid’ is imported by ‘gtable’ so cannot be unloaded 
Error in unloadNamespace(tounload[i]) : 
    namespace ‘labeling’ is imported by ‘scales’ so cannot be unloaded 
Error in unloadNamespace(tounload[i]) : 
    namespace ‘munsell’ is imported by ‘scales’ so cannot be unloaded 

Answer 1

Questo funziona per me - un po 'grezzo, ma ottiene il lavoro fatto.

on.exit({ 
    #reset time limit 
    setTimeLimit(cpu=Inf, elapsed=Inf, transient=FALSE); 

    #try to detach packages that were attached during eval 
    nowattached <- search(); 
    todetach <- nowattached[!(nowattached %in% currentlyattached)]; 
    while(! length(todetach) == 0){ 
    for(i in seq_along(todetach)){ 
     suppressWarnings(tryCatch(detach(todetach[i], unload=TRUE, character.only=TRUE, force=TRUE),error = function(x) return(NA))) 
    } 
    nowattached <- search(); 
    todetach <- sample(nowattached[!(nowattached %in% currentlyattached)]); 
    } 

    #try to unload packages that are still loaded 
    nowloaded <- loadedNamespaces(); 
    tounload <- nowloaded[!(nowloaded %in% currentlyloaded)]; 
    while(! length(tounload) == 0){ 
    for(i in seq_along(todetach)){ 
     suppressWarnings(tryCatch(unloadNamespace(tounload[i]),error = function(x) return(NA))) 
    } 
    nowloaded <- loadedNamespaces(); 
    tounload <- sample(nowloaded[!(nowloaded %in% currentlyloaded)]); 
    } 
});