Pure functions as a replacement of constant mappings?
I need to create a lookup table [uint -> uint] that is constant.
Constant mappings or switch-case are not available in solidity. Are pure functions full of if-else the only option?
Any better suggestion?
Update Ideally, I would like an option that minimizes gas utilization
solidity mapping pure
asked Jan 2 at 21:03
purpletentacle
1164
add a comment |
I need to create a lookup table [uint -> uint] that is constant.
Constant mappings or switch-case are not available in solidity. Are pure functions full of if-else the only option?
Any better suggestion?
Update Ideally, I would like an option that minimizes gas utilization
solidity mapping pure
asked Jan 2 at 21:03
purpletentacle
1164
It seems from discussion below that this question is about gas optimization.
– smarx
Jan 2 at 23:48
add a comment |
I need to create a lookup table [uint -> uint] that is constant.
Constant mappings or switch-case are not available in solidity. Are pure functions full of if-else the only option?
Any better suggestion?
Update Ideally, I would like an option that minimizes gas utilization
solidity mapping pure
asked Jan 2 at 21:03
purpletentacle
1164
I need to create a lookup table [uint -> uint] that is constant.
Constant mappings or switch-case are not available in solidity. Are pure functions full of if-else the only option?
Any better suggestion?
Update Ideally, I would like an option that minimizes gas utilization
solidity mapping pure
solidity mapping pure
asked Jan 2 at 21:03
purpletentacle
1164
asked Jan 2 at 21:03
purpletentacle
1164
edited 2 days ago
asked Jan 2 at 21:03
purpletentacle
1164
asked Jan 2 at 21:03
purpletentacle
1164
asked Jan 2 at 21:03
purpletentacle
1164
1164
It seems from discussion below that this question is about gas optimization.
– smarx
Jan 2 at 23:48
add a comment |
It seems from discussion below that this question is about gas optimization.
– smarx
Jan 2 at 23:48
It seems from discussion below that this question is about gas optimization.
– smarx
Jan 2 at 23:48
It seems from discussion below that this question is about gas optimization.
– smarx
Jan 2 at 23:48
add a comment |
2 Answers
2
active
oldest
votes
I don't see a dilemma.
You can have a mapping:
mapping(uint => uint) public myMap;
You can populate some locations in the constructor or elsewhere:
constructor() public {
myMap[1] = 101;
myMap[2] = 201;
}
That gives you a simple view function (myMap(uint) public view returns(uint)) that returns the number stored at an index.
You can also make view functions full of if/else if that's the best approach for your use-case.
Elaborate on the question with some hints about what you want to accomplish and possibly more specific guidance will be possible.
Hope it helps.
answered Jan 2 at 21:12
Rob Hitchens B9lab
26k54379
Well, clearly I want to minimize gas. What do you think would be more efficient?
– purpletentacle
Jan 2 at 23:14
add a comment |
The else-if function is by far less efficient that mapping in case of sparse data if there are not special criteria for searching.
If, on the contrary, you fill all the holes in the range of interest, a simple array is the best solution.
answered Jan 3 at 0:29
Rick Park
825111
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
I don't see a dilemma.
You can have a mapping:
mapping(uint => uint) public myMap;
You can populate some locations in the constructor or elsewhere:
constructor() public {
myMap[1] = 101;
myMap[2] = 201;
}
That gives you a simple view function (myMap(uint) public view returns(uint)) that returns the number stored at an index.
You can also make view functions full of if/else if that's the best approach for your use-case.
Elaborate on the question with some hints about what you want to accomplish and possibly more specific guidance will be possible.
Hope it helps.
answered Jan 2 at 21:12
Rob Hitchens B9lab
26k54379
Well, clearly I want to minimize gas. What do you think would be more efficient?
– purpletentacle
Jan 2 at 23:14
add a comment |
I don't see a dilemma.
You can have a mapping:
mapping(uint => uint) public myMap;
You can populate some locations in the constructor or elsewhere:
constructor() public {
myMap[1] = 101;
myMap[2] = 201;
}
That gives you a simple view function (myMap(uint) public view returns(uint)) that returns the number stored at an index.
You can also make view functions full of if/else if that's the best approach for your use-case.
Elaborate on the question with some hints about what you want to accomplish and possibly more specific guidance will be possible.
Hope it helps.
answered Jan 2 at 21:12
Rob Hitchens B9lab
26k54379
Well, clearly I want to minimize gas. What do you think would be more efficient?
– purpletentacle
Jan 2 at 23:14
add a comment |
I don't see a dilemma.
You can have a mapping:
mapping(uint => uint) public myMap;
You can populate some locations in the constructor or elsewhere:
constructor() public {
myMap[1] = 101;
myMap[2] = 201;
}
That gives you a simple view function (myMap(uint) public view returns(uint)) that returns the number stored at an index.
You can also make view functions full of if/else if that's the best approach for your use-case.
Elaborate on the question with some hints about what you want to accomplish and possibly more specific guidance will be possible.
Hope it helps.
answered Jan 2 at 21:12
Rob Hitchens B9lab
26k54379
I don't see a dilemma.
You can have a mapping:
mapping(uint => uint) public myMap;
You can populate some locations in the constructor or elsewhere:
constructor() public {
myMap[1] = 101;
myMap[2] = 201;
}
That gives you a simple view function (myMap(uint) public view returns(uint)) that returns the number stored at an index.
You can also make view functions full of if/else if that's the best approach for your use-case.
Elaborate on the question with some hints about what you want to accomplish and possibly more specific guidance will be possible.
Hope it helps.
answered Jan 2 at 21:12
Rob Hitchens B9lab
26k54379
answered Jan 2 at 21:12
Rob Hitchens B9lab
26k54379
answered Jan 2 at 21:12
Rob Hitchens B9lab
26k54379
answered Jan 2 at 21:12
Rob Hitchens B9lab
26k54379
26k54379
Well, clearly I want to minimize gas. What do you think would be more efficient?
– purpletentacle
Jan 2 at 23:14
add a comment |
Well, clearly I want to minimize gas. What do you think would be more efficient?
– purpletentacle
Jan 2 at 23:14
Well, clearly I want to minimize gas. What do you think would be more efficient?
– purpletentacle
Jan 2 at 23:14
Well, clearly I want to minimize gas. What do you think would be more efficient?
– purpletentacle
Jan 2 at 23:14
add a comment |
The else-if function is by far less efficient that mapping in case of sparse data if there are not special criteria for searching.
If, on the contrary, you fill all the holes in the range of interest, a simple array is the best solution.
answered Jan 3 at 0:29
Rick Park
825111
add a comment |
The else-if function is by far less efficient that mapping in case of sparse data if there are not special criteria for searching.
If, on the contrary, you fill all the holes in the range of interest, a simple array is the best solution.
answered Jan 3 at 0:29
Rick Park
825111
add a comment |
The else-if function is by far less efficient that mapping in case of sparse data if there are not special criteria for searching.
If, on the contrary, you fill all the holes in the range of interest, a simple array is the best solution.
answered Jan 3 at 0:29
Rick Park
825111
The else-if function is by far less efficient that mapping in case of sparse data if there are not special criteria for searching.
If, on the contrary, you fill all the holes in the range of interest, a simple array is the best solution.
answered Jan 3 at 0:29
Rick Park
825111
answered Jan 3 at 0:29
Rick Park
825111
answered Jan 3 at 0:29
Rick Park
825111
answered Jan 3 at 0:29
Rick Park
825111
825111
add a comment |
add a comment |
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It seems from discussion below that this question is about gas optimization.
– smarx
Jan 2 at 23:48