Concatenate a list of strings using a comma in Bash

concatenate_with_commas.sh

#########################################
## Concatenate a list of arguments with commas
##
## Outputs:
##   Outputs all arguments as a single string, concatenated with commas
#########################################
concatenate_with_commas() {
    local concatenated=""
    local string

    for string in "$@"; do
        if [[ "${concatenated}" == "" ]]; then
            concatenated+="${string}"
        else
            concatenated+=",${string}"
        fi
    done

    echo "${concatenated}"
}