Monomorphization

In programming languages, monomorphization is a compile-time process where polymorphic functions are replaced by many monomorphic functions for each unique instantiation.^[1] It is considered beneficial to undergo the mentioned transformation because it results in the output intermediate representation (IR) having specific types, which allows for more effective optimization. Additionally, many IRs are intended to be low-level and do not accommodate polymorphism. The resulting code is generally faster than dynamic dispatch, but may require more compilation time and storage space due to duplicating the function body.^{[2][3][4][5][6][7]}

Example

This is an example of a use of a generic identity function in Rust

fn id<T>(x: T) -> T {  return x; } fn main() {  let int = id(10);  let string = id("some text");  println!("{int}, {string}"); } 

After monomorphization, this would become equivalent to

fn id_i32(x: i32) -> i32 {  return x; } fn id_str(x: &str) -> &str {  return x; } fn main() {  let int = id_i32(10);  let string = id_str("some text");  println!("{int}, {string}"); } 

See also

• Parametric polymorphism
• Type erasure
• Template (C++)

References

1. "Generic Data Types - The Rust Programming Language". Retrieved 27 May 2021.
2. Hume, Tristan. "Models of Generics and Metaprogramming: Go, Rust, Swift, D and More". Retrieved 27 May 2021.
3. Tanaka, Akira; Affeldt, Reynald; Garrigue, Jacques (2018). "Safe Low-level Code Generation in Coq Using Monomorphization and Monadification". Journal of Information Processing. 26: 54–72. doi:10.2197/ipsjjip.26.54.
4. "Extending Smt-Lib v2 with λ-Terms and Polymorphism". CiteSeerX 10.1.1.663.6849. {{cite journal}}: Cite journal requires |journal= (help)
5. Cai, Yufei; Giarrusso, Paolo G.; Ostermann, Klaus (2016-01-11). "System f-omega with equirecursive types for datatype-generic programming". Proceedings of the 43rd Annual ACM SIGPLAN-SIGACT Symposium on Principles of Programming Languages. POPL '16. St. Petersburg, FL, USA: Association for Computing Machinery. pp. 30–43. doi:10.1145/2837614.2837660. ISBN 978-1-4503-3549-2. S2CID 17566568.
6. Klabnik, Steve; Nichols, Carol (2019-08-06). The Rust Programming Language (Covers Rust 2018). No Starch Press. ISBN 978-1-7185-0044-0.
7. Felty, Amy P.; Middeldorp, Aart (2015-07-30). Automated Deduction - CADE-25: 25th International Conference on Automated Deduction, Berlin, Germany, August 1-7, 2015, Proceedings. Springer. ISBN 978-3-319-21401-6.