Define all functions in one .R file, call them from another .R file. How, if possible?

r file scope namespaces user-defined-functions

You can call source("abc.R") followed by source("xyz.R") (assuming that both these files are in your current working directory.

If abc.R is:

fooABC <- function(x) {    k <- x+1    return(k)}

and xyz.R is:

fooXYZ <- function(x) {    k <- fooABC(x)+1    return(k)}

then this will work:

> source("abc.R")> source("xyz.R")> fooXYZ(3)[1] 5>

Even if there are cyclical dependencies, this will work.

E.g. If abc.R is this:

fooABC <- function(x) {    k <- barXYZ(x)+1    return(k)}barABC <- function(x){    k <- x+30    return(k)}

and xyz.R is this:

fooXYZ <- function(x) {    k <- fooABC(x)+1    return(k)}barXYZ <- function(x){    k <- barABC(x)+20    return(k)}

then,

> source("abc.R")> source("xyz.R")> fooXYZ(3) [1] 55>

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