const

Constants are evaluated at compile time and their values are inlined wherever they are used:

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

Gemäß dem Rust RFC Book werden diese bei der Verwendung eingefügt (inlined upon use).

Only functions marked const can be called at compile time to generate const values. const functions can however be called at runtime.

Speaker Notes

  • Mention that const behaves semantically similar to C++'s constexpr
  • Es kommt nicht sehr häufig vor, dass man eine zur Laufzeit ausgewertete Konstante benötigt, aber es ist hilfreich und sicherer als die Verwendung einer statischen.