Command line arguments parsing in ballerina similar to argparse in python - parsing

Question

Is there any way to parse the command line arguments in ballerina? From what I have seen you can use only positional arguments. What I would like to do is something like this:
//main.bal
public function main(string? name, int? age) returns error? {
if (name is string && age is int) {
io:println("Hello " + name);
io:println("Age " + age.toString());
}
}
And then run the programm as follows:
bal run main.bal -- --name John --age=18
But this does not work, because it takes "--name" as the first positional argument and "John" as the second positional argument. So it throws an error:
error: invalid argument 'John' for parameter 'age', expected integer value
And if I run it as follows then it runs:
bal run main.bal -- John 18

Answer 1

The arguments can be passed by name if they are specified for options.
If the arguments are part of a record like
public type Details record {|
string name?;
int age?;
|};
and the main function has an included record parameter of this type to specify options
public function main(*Details f) {
string? name = f?.name;
int? age = f?.age;
if name is string && age is int {
io:println("Hello ", name);
io:println("Age ", age);
}
}
it can be run as follows
$ bal run main.bal -- --name=Jo --age=25
This was introduced in Swan Lake Alpha5 and the release note provides more information - https://ballerina.io/downloads/swan-lake-release-notes/swan-lake-alpha5/#improved-command-line-argument-parsing.

Answer 2

You can use configurable support for this.
Check this example:
import ballerina/io;
configurable string name = ?;
configurable int age = ?;
public function main() returns error? {
io:println("Hello " + name);
io:println("Age " + age.toString());
}
Then while running you can provide values as following:
bal run main.bal -- -Cname="Ballerina" -Cage=5
The result is
Hello Ballerina
Age 5
Check this guide for more details.