[R] Combining series of variables using identifier

[Lauri Nikkinen]

R users,

I have df like this

a <- data.frame(    indx =    1:20,
                    var1 =    rep(c("I20", "I40", "A50", "B60"), each=5),
                    var1_lab= rep(c("cat", "dog", "mouse", "horse"), each=5),
                    var2 =    rep(c("B20", "X40", "D50", "G60"), each=5),
                    var2_lab= rep(c("car", "bicycle", "train", "bus"), each=5))
str(a)

I'd like to create new variables by combining "varX" and "varX_lab" like this:

a$var1_new <- factor(paste(a$var1, a$var1_lab, sep=": "))
a$var2_new <- factor(paste(a$var2, a$var2_lab, sep=": "))
a

But, in the real world, I have multiple df:s and many of variables
named by the same manner. Is there a possibility to create a function
which combines these variables and creates new ones into the same df
using "varX" as an identifier?

Many thanks,
Lauri