Managing class and their order

# result is of class character; it prints correctly

result <- "Je suis donc je pense"

class(result)

print(result)

# I add a new class but I keep character class. All is ok

# The order of classes is not important because there is no print() function for class ECFOCF

class(result) <- unique(append(class(result),"ECFOCF")))

class(result)

print(result)

result <- "Je suis donc je pense"

class(result) <- unique(append("ECFOCF", class(result)))

class(result)

print(result)

# I create a new function for class ECFOCF

# This function is used in priority whatever the ordre of classes

print.ECFOCF <- function(x) {cat("print.ECFOCF ", x)}

result <- "Je suis donc je pense"

print(result)

class(result) <- unique(append(class(result),"ECFOCF")))

class(result)

print(result)

result <- "Je suis donc je pense"

class(result) <- unique(append("ECFOCF", class(result)))

class(result)

print(result)

# I create a new function for class CF

# The function used in priority depends on the order of classes

print.CF <- function(x) {cat("print.CF ", x)}

result <- "Je suis donc je pense"

class(result) <- unique(append("ECFOCF", class(result)))

class(result)

print(result)

class(result) <- unique(append("CF", class(result)))

class(result)

print(result)

result <- "Je suis donc je pense"

class(result) <- unique(append("CF", class(result)))

class(result)

print(result)

class(result) <- unique(append("ECFOCF", class(result)))

class(result)

print(result)