Homework 1 #4
Homework 1 #4
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| let a: u64 = | ||
| self.fed - (HUNGER_PER_BLOCK as u64) * ((exec::block_height() as u64) - self.fed_block); | ||
| a |
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No need to create a var:
| let a: u64 = | |
| self.fed - (HUNGER_PER_BLOCK as u64) * ((exec::block_height() as u64) - self.fed_block); | |
| a | |
| self.fed - HUNGER_PER_BLOCK * ((exec::block_height() as u64) - self.fed_block) |
| impl Tamagotchi { | ||
| fn current_fed(&mut self) -> u64 { | ||
| let a: u64 = | ||
| self.fed - (HUNGER_PER_BLOCK as u64) * ((exec::block_height() as u64) - self.fed_block); |
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If self.fed is less than HUNGER_PER_BLOCK * (exec::block_height() - self.fed_block), then subtraction results in the underflow.
| let birthdate = exec::block_height() as u64; | ||
| let fedblock = exec::block_height() as u64; | ||
| let entertainedblock = exec::block_height() as u64; | ||
| let sleptblock = exec::block_height() as u64; |
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There is no need to call exec::block_height multiple times as it is quite expensive. Better is to get block height one time and copy it.
| tmg.slept = tmg.current_slept(); | ||
| } else { | ||
| let fedblock = exec::block_height() as u64; | ||
| tmg.fed = 10000; |
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It is better to use named constants for numbers.
| tmg.entertained = tmg.current_entertained(); | ||
| tmg.slept = tmg.current_slept(); |
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The same code is in both if branches.
| } | ||
| fn current_entertained(&mut self) -> u64 { | ||
| let b: u64 = self.entertained | ||
| - (BOREDOM_PER_BLOCK as u64) * ((exec::block_height() as u64) - self.entertained_block); |
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Using self.entertained_block is not correct here. We need to save the last processed block height here.
| - (BOREDOM_PER_BLOCK as u64) * ((exec::block_height() as u64) - self.entertained_block); | |
| - (BOREDOM_PER_BLOCK as u64) * ((exec::block_height() as u64) - last_processed_block); |
| tmg.fed = tmg.current_fed(); | ||
| tmg.entertained = tmg.current_entertained(); |
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Anyway, you can move the fed / entertained / slept decreasing outside this match.
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| let _result = program.send(1, TmgAction::Sleep); | ||
| //how to test the panic result? | ||
| //negetive test |
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It would be great to check the Tamagotchi's vital signs after spending various counts of blocks.
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