# \#fp

**URL:** https://discuss.ocaml.org/tag/fp/752.md

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## [What is the significance of a 'witness' in OCaml(or FP)?](https://discuss.ocaml.org/t/what-is-the-significance-of-a-witness-in-ocaml-or-fp/18051)

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**Author:** [@Mohan\_Radhakrishnan](https://discuss.ocaml.org/u/Mohan_Radhakrishnan)\
**Replies:** 4\
**Last updated:** [May 11, 2026, 2:22pm UTC](https://discuss.ocaml.org/t/what-is-the-significance-of-a-witness-in-ocaml-or-fp/18051 "2026-05-11T14:22:28Z")

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Hello, I came across this term when I was following the new Java features(Screenshot is attached). It was a JVMLS session. Dreading to ask as my FP knowledge is minimal but even Java is introducing these. I also looked …