28 lines
1.2 KiB
Markdown
28 lines
1.2 KiB
Markdown
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# Function statement
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Function statement is used to define a function. See eg, below for a function which adds 2 numbers
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```
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Function ADD(x uint64, y uint64) uint64
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10 RETURN x + y
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End Function
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```
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Function syntax is of 2 types
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1. Function function_name( 0 or more arguments )
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2. Function function_name( 0 or more arguments ) return type
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The rules for functions are as follows
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* All functions begin with Function keyword
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* Function name should be alpha-numeric. If the first letter of the function is Upper case alphabet, it can be invoked by blockchain and other smart-contracts. Otherwise the function can only be called by other functions within the smart contract.
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* Function may or may not have a return type
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* All functions must use RETURN to return from function or to return a value. RETURN is mandatory.
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* All functions must end with End Function. End Function is mandatory
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* A function can have a implicit parameter value of type uint64, which contains amount of DERO value sent with the transaction.
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Any error caused during processing will immediately stop execution and discard all changes that occur during SC execution.
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Any Entrypoint which returns uint64 value 0 is termed as success and will make transaction to commit all state changes.
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