require() vs assert().md

52 - require() vs assert()

require() should be used for checking error conditions on inputs and return values while assert() should be used for invariant checking. Between solc 0.4.10 and 0.8.0, require() used REVERT (0xfd) opcode which refunded remaining gas on failure while assert() used INVALID (0xfe) opcode which consumed all the supplied gas. (see here)

---

Slide Screenshot

---

Slide Text

• assert() vs require() -> Different Usages
• assert() -> Invariants
• No Failures Expected
• require() -> Validation Failures Expected
• Use Appropriately

---

References

• Youtube Reference

---

Tags