Solidity Programming Essentials

Modifiers

In Solidity, a modifier is always associated with a function. A modifier in programming languages refers to a construct that changes the behavior of the executing code. Since a modifier is associated with a function in Solidity, it has the power to change the behavior of functions that it is associated with. For easy understanding of modifiers, think of them as a function that will be executed before execution of the target function. Suppose you want to invoke the getAge function but, before executing it, you would like to execute another function that could check the current state of the contract, values in incoming parameters, the current value in state variables, and so on and accordingly decide whether the target function