How do I handle retry logic for unreliable external resources?

Using multiple parameters and multiple returns

The function handles multiple arguments and multiple returns.

Multiple Arguments [top]

The function supports multiple arguments, in the form: arg1, arg2,… argN.

Note: Arguments with other names will raise an error:

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Multiple Returns [top]

Lua functions can return multiple values from a function, supports this language feature:

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Note: When an error occurs there will be only two returns, the first is the error message and the second (last) is the informational message:

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Tip: The code that achieves the multiple returns is a bit subtle.

The returns from pcall() are assigned to a table “R”:

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Which is is then unpacked when it is returned from

Screen Shot 2014-03-04 at 16.47.24

Note: unpack() is a standard Lua function that returns the elements from a table.

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