Assign a value to character named variable with index - r

Question

I know we can use assign to assign values to a character name vector. For example
assign("target",1:5)
However, if we want to change the 1st element of the target(target can be a vector/matrix/list), how should we do that? target here can also be a matrix, so we can change one element, one row or one column.
I want to do something like
target[1] <- 99
if I use
assign("target[1]",99)
it will only generate a new object named target[1] and value is 99. Here is a simple and trial example
# This function is meaningless, just used to show my situation
# variable_name is a character
example_function <- function(variable_name){
assign(variable_name,1:5)
if(rnorm(1)>1){
variable_name[1] <- 99 #This will not work and I just need some function to achive this purpose
}
}
example_function("justAname")

Answer 1

As an alternative approach you could use the [<- function.
f = function(variable_name){
assign(variable_name,1:5)
if(rnorm(1)>1){
`[<-`(eval(as.name(variable_name)),i = 1, value = 99)
}
get(variable_name)
}
This should also work with matrices
f_mat = function(variable_name){
assign(variable_name,matrix(1:25,nrow = 5))
if(rnorm(1)>1){
`[<-`(eval(as.name(variable_name)),i = 1, j = , value = 99) # for 1st row
# `[<-`(eval(as.name(variable_name)),i = , j = 1, value = 99) # for 1st col
#specify i and j for ith row jth column
}
get(variable_name)
}
and lists similarly.