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Shlok Kumar
Shlok Kumar

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Do-while Loop in Solidity

The "do-while" loop in Solidity is a control flow statement that executes its block of code at least once and repeatedly executes as long as the condition specified remains true.

Do-while loop is quite similar to the while loop with the exception that there is a condition check after the loop, which means that the loop will always execute at least once even if the condition is false.

The do-while loop in Solidity is a control flow statement that allows developers to execute a block of code repeatedly until a specified condition is met. This loop differs from the while loop in that the code block is guaranteed to be executed at least once. The syntax of the do-while loop in Solidity is similar to that of other programming languages, with the addition of the "require" statement to ensure that the condition is met before continuing to the next iteration.

The do-while loop is useful for situations where a certain action must be taken at least once, regardless of the value of the condition. For example, if you want to ensure that a certain balance is maintained in a contract, you could use a do-while loop to check the balance and make the necessary transfers to maintain the balance. In this case, the loop would be executed at least once, even if the balance was already sufficient.

When using do-while loops in Solidity, it is important to be mindful of the gas consumption, as each iteration of the loop will require a certain amount of gas. If the loop condition is not met in a reasonable amount of time, it could lead to an out-of-gas error, which could cause the entire transaction to fail. Additionally, care should be taken to ensure that the loop condition is well-defined and will eventually be met, otherwise the loop could run indefinitely, leading to an infinite loop error. To avoid these issues, it is best to test do-while loops thoroughly before deploying them to the main network.

do

Syntax:

do 
{
   block of statements to be executed
} while 
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Do-while loop example

//SPDX-License-Identifier:MIT
pragma solidity ^0.8.0; 

// Creating a contract 
contract Types { 
      
    // Declaring a dynamic array
    uint[] data; 
    
    // Declaring state variable
    uint8 j = 0;
  
    // Defining function to demonstrate 
    // 'Do-While loop'
    function loop(
    ) public returns(uint[] memory){
    do{
        j++;
        data.push(j);
     }while(j < 5) ;
      return data;
    }
} 
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