Mixing
Can anyone please explain me the following solidity code?
What is the use of -1 in instructorAccts.push(_address) -1?
function setInstructor(address _address, uint _age, string _fName, string _lName) public {
var instructor = instructors[_address];
instructor.age = _age;
instructor.fName = _fName;
instructor.lName = _lName;
instructorAccts.push(_address) -1;
}
solidity
edited Jan 27 at 20:58
Rosco Kalis
1,1111421
asked Jan 27 at 7:49
Saiteja KuruvaSaiteja Kuruva
165
add a comment |
What is the use of -1 in instructorAccts.push(_address) -1?
function setInstructor(address _address, uint _age, string _fName, string _lName) public {
var instructor = instructors[_address];
instructor.age = _age;
instructor.fName = _fName;
instructor.lName = _lName;
instructorAccts.push(_address) -1;
}
solidity
edited Jan 27 at 20:58
Rosco Kalis
1,1111421
asked Jan 27 at 7:49
Saiteja KuruvaSaiteja Kuruva
165
2
See ethereum.stackexchange.com/questions/40312/…
– ivicaa
Jan 27 at 8:01
My guess is-1was blindly copied from another example.push()-1corresponds to the row in the array occupied by the appended element. As @goodvibration points out, the result of this work isn't assigned to anything (e.g.uint position = array.push(value) -1) so the extra work is pointless.
– Rob Hitchens
Jan 27 at 22:19
add a comment |
What is the use of -1 in instructorAccts.push(_address) -1?
function setInstructor(address _address, uint _age, string _fName, string _lName) public {
var instructor = instructors[_address];
instructor.age = _age;
instructor.fName = _fName;
instructor.lName = _lName;
instructorAccts.push(_address) -1;
}
solidity
edited Jan 27 at 20:58
Rosco Kalis
1,1111421
asked Jan 27 at 7:49
Saiteja KuruvaSaiteja Kuruva
165
What is the use of -1 in instructorAccts.push(_address) -1?
function setInstructor(address _address, uint _age, string _fName, string _lName) public {
var instructor = instructors[_address];
instructor.age = _age;
instructor.fName = _fName;
instructor.lName = _lName;
instructorAccts.push(_address) -1;
}
solidity
solidity
edited Jan 27 at 20:58
Rosco Kalis
1,1111421
asked Jan 27 at 7:49
Saiteja KuruvaSaiteja Kuruva
165
edited Jan 27 at 20:58
Rosco Kalis
1,1111421
asked Jan 27 at 7:49
Saiteja KuruvaSaiteja Kuruva
165
edited Jan 27 at 20:58
Rosco Kalis
1,1111421
edited Jan 27 at 20:58
Rosco Kalis
1,1111421
edited Jan 27 at 20:58
Rosco Kalis
1,1111421
1,1111421
asked Jan 27 at 7:49
Saiteja KuruvaSaiteja Kuruva
165
asked Jan 27 at 7:49
Saiteja KuruvaSaiteja Kuruva
165
asked Jan 27 at 7:49
Saiteja KuruvaSaiteja Kuruva
165
165
2
See ethereum.stackexchange.com/questions/40312/…
– ivicaa
Jan 27 at 8:01
My guess is-1was blindly copied from another example.push()-1corresponds to the row in the array occupied by the appended element. As @goodvibration points out, the result of this work isn't assigned to anything (e.g.uint position = array.push(value) -1) so the extra work is pointless.
– Rob Hitchens
Jan 27 at 22:19
add a comment |
2
See ethereum.stackexchange.com/questions/40312/…
– ivicaa
Jan 27 at 8:01
My guess is-1was blindly copied from another example.push()-1corresponds to the row in the array occupied by the appended element. As @goodvibration points out, the result of this work isn't assigned to anything (e.g.uint position = array.push(value) -1) so the extra work is pointless.
– Rob Hitchens
Jan 27 at 22:19
2
2
See ethereum.stackexchange.com/questions/40312/…
– ivicaa
Jan 27 at 8:01
See ethereum.stackexchange.com/questions/40312/…
– ivicaa
Jan 27 at 8:01
My guess is
-1 was blindly copied from another example. push()-1 corresponds to the row in the array occupied by the appended element. As @goodvibration points out, the result of this work isn't assigned to anything (e.g. uint position = array.push(value) -1) so the extra work is pointless.– Rob Hitchens
Jan 27 at 22:19
My guess is
-1 was blindly copied from another example. push()-1 corresponds to the row in the array occupied by the appended element. As @goodvibration points out, the result of this work isn't assigned to anything (e.g. uint position = array.push(value) -1) so the extra work is pointless.– Rob Hitchens
Jan 27 at 22:19
add a comment |
1 Answer
1
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oldest
votes
The expression instructorAccts.push(_address) equals to the length of the instructorAccts array after pushing the _address item into it.
The expression instructorAccts.push(_address) - 1 equals to the length of the instructorAccts array before pushing the _address item into it.
In your example, since this value is not stored or used in any manner, this expression has no effect.
answered Jan 27 at 8:00
goodvibrationgoodvibration
4,26411024
add a comment |
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1 Answer
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active
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1 Answer
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active
oldest
votes
active
oldest
votes
active
oldest
votes
The expression instructorAccts.push(_address) equals to the length of the instructorAccts array after pushing the _address item into it.
The expression instructorAccts.push(_address) - 1 equals to the length of the instructorAccts array before pushing the _address item into it.
In your example, since this value is not stored or used in any manner, this expression has no effect.
answered Jan 27 at 8:00
goodvibrationgoodvibration
4,26411024
add a comment |
The expression instructorAccts.push(_address) equals to the length of the instructorAccts array after pushing the _address item into it.
The expression instructorAccts.push(_address) - 1 equals to the length of the instructorAccts array before pushing the _address item into it.
In your example, since this value is not stored or used in any manner, this expression has no effect.
answered Jan 27 at 8:00
goodvibrationgoodvibration
4,26411024
add a comment |
The expression instructorAccts.push(_address) equals to the length of the instructorAccts array after pushing the _address item into it.
The expression instructorAccts.push(_address) - 1 equals to the length of the instructorAccts array before pushing the _address item into it.
In your example, since this value is not stored or used in any manner, this expression has no effect.
answered Jan 27 at 8:00
goodvibrationgoodvibration
4,26411024
The expression instructorAccts.push(_address) equals to the length of the instructorAccts array after pushing the _address item into it.
The expression instructorAccts.push(_address) - 1 equals to the length of the instructorAccts array before pushing the _address item into it.
In your example, since this value is not stored or used in any manner, this expression has no effect.
answered Jan 27 at 8:00
goodvibrationgoodvibration
4,26411024
answered Jan 27 at 8:00
goodvibrationgoodvibration
4,26411024
answered Jan 27 at 8:00
goodvibrationgoodvibration
4,26411024
answered Jan 27 at 8:00
goodvibrationgoodvibration
4,26411024
4,26411024
add a comment |
add a comment |
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2
See ethereum.stackexchange.com/questions/40312/…
– ivicaa
Jan 27 at 8:01
My guess is
-1was blindly copied from another example.push()-1corresponds to the row in the array occupied by the appended element. As @goodvibration points out, the result of this work isn't assigned to anything (e.g.uint position = array.push(value) -1) so the extra work is pointless.– Rob Hitchens
Jan 27 at 22:19