5aed8b3ef5
Functions must be annotated as `stateful` in order to - Update the contract state (using `put`) - Call `Chain.spend` or other primitive functions that cost tokens - Call an Oracle or AENS function that requires a signature - Make a remote call with a non-zero value - Construct a lambda calling a stateful function It does not need to be stateful to - Read the contract state - Call another contract with value=0, even when the remote function is stateful
18 lines
470 B
Plaintext
18 lines
470 B
Plaintext
// An implementation of the factorial function where each recursive
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// call is to another contract. Not the cheapest way to compute factorial.
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contract FactorialServer =
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function fac : (int) => int
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contract Factorial =
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record state = {worker : FactorialServer}
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function init(worker) = {worker = worker}
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stateful function set_worker(worker) = put(state{worker = worker})
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function fac(x : int) : int =
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if(x == 0) 1
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else x * state.worker.fac(x - 1)
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