The Complete Solidity Course - Zero to Advanced for Blockchain and Smart Contracts - Visibility - Public Private Interna

The video tutorial covers the concept of function visibility and variable scope in Solidity. It explains the use of keywords like private, public, external, and internal to define the accessibility of functions and variables. The tutorial also differentiates between state and local variables, demonstrating how scope affects data accessibility within a contract. Practical examples illustrate how to compile and deploy contracts, emphasizing the importance of specifying visibility to access functions and data outside the contract.

Which of the following is NOT a keyword used to define scope in Solidity?

• external

• global

• public

• private

What is the main limitation of local variables in Solidity?

• They can only be accessed within the function they are declared in.

• They can be accessed by any function in the contract.

• They are automatically public.

• They are stored permanently on the blockchain.

How can you make a variable accessible in multiple functions within a contract?

• Declare it as a global variable.

• Use the 'external' keyword.

• Move it outside the functions to make it a state variable.

• Declare it as a local variable in each function.

What must be specified for functions to avoid visibility-related compiler errors?

• The data type of the function.

• The visibility and mutability of the function.

• The return value of the function.

• The name of the function.

What happens when you add the 'public' keyword to a variable in Solidity?

• It becomes accessible outside the contract.

• It becomes immutable.

• It becomes a global variable.

• It becomes a local variable.

Which of the following is true about global variables in Solidity?

• They are declared by the user.

• They require the 'global' keyword.

• They are built into Solidity and can be accessed globally.

• They are only accessible within the contract.

What is the effect of making a function public in Solidity?

• It is automatically executed on contract deployment.

• It becomes a local function.

• It can be called from outside the contract.

• It can only be called within the contract.