It's not too tricky. The rand statement imposes a scalar context on @Chars, so it gets a random number bounded by the number of elements in the array.

The map statement creates a 30 element list of those random numbers.

That list is used as indexes into an array slice. (That means that the second argument to the join statement is a random set of 30 characters from the @Chars array.) They're joined into a string.

In reply to Random Array Slice by chromatic
in thread Random number by Moshambo

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