find the index of a substring within a string in R

str <- "Hello world, I'm a programmer" 
index <- gregexpr("programmer", str)[[1]][1] 
print(index)

This code will return the index of the substring “programmer” within the string “Hello world, I’m a programmer”. The first line of the code assigns the string “Hello world, I’m a programmer” to a variable named “str”. Then, the function “gregexpr()” is used to find the index of the substring “programmer” within the string stored in the variable “str”. The result of the function is stored in the variable “index”. Finally, the index is printed on the screen using the “print” command.