Two functions with the same name in two different packages

We have two functions with the same name in two different packages. For example: do you need to load two R packages : tseries and chron? They both have a function named is.weekend I always have in my environment the function from the second package I loaded. How can I access always the function from chron package?

You have probably already noticed that the order of loading the packages makes a difference, i.e. the package that gets loaded last will mask the functions in packages loaded earlier.

To specify the package that you want to use, the syntax is following package::function.name() Alternatively you can re-name the function from the package loaded first (with is.weekend.chron <- is.weekend), then both functions are available (under names is.weekend.chron and is.weekend).

chron::is.weekend()
tseries::is.weekend()

#In other words, use 
packagename::functionname()
#In addition, if you know that you will always want to use the function in chron, #you can define your own function as follows:
is.weekend <- chron::is.weekend #EDIT

library(chron)
is.weekend.chron <- is.weekend
library(tseries)
# then you can call is.weekend for the tseries version or is.weekend.chron for the chron version