Ethereum-Solidity Quiz Q18: What type of modifiers are "view" and "pure"?

They are not visibility modifiers, they're state mutability modifiers.

State Mutability Modifiers describe whether a function reads or modifies state.

"view"

• Can read state variables
• Cannot modify state
• Cannot emit events (technically they can in newer versions, but it's not very common)
• Does not consume gas (when called externally)
• Must return a value

"pure"

• Cannot read state variables
• Cannot modify state
• Cannot emit events
• Does not consume gas (when called externally)
• Can only use function parameters and local variables
• Must return a value

Default (no modifier)

• Can read state
• Can modify state
• Can emit events
• Costs gas to execute
• State-changing function

Aspect	Default	view	pure
Read state	✅	✅	❌
Modify state	✅	❌	❌
Emit events	✅	✅	❌
Costs gas	✅	❌ (external)	❌ (external)
Use parameters	✅	✅	✅