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NPL (programming language) — Wikipedia (en)

Source: Wikipedia (en)
Original: https://en.wikipedia.org/wiki/NPL_(programming_language)
License (as archived): CC-BY-SA-4.0
Archived: 2026-10-08T00:11:23.520Z
SHA-256 of the archived text: fafe69b6c39c7c818902555fa517690c085b8545778122557535b549d688d651
Stable URL of this page: https://metraipolis.com/documento/dc_4e3fb76bb109

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NPL (programming language) — Wikipedia (en) — Wikipedia (en), https://en.wikipedia.org/wiki/NPL_(programming_language) (CC-BY-SA-4.0); archived copy: https://metraipolis.com/documento/dc_4e3fb76bb109 (Metraipolis archive dc_4e3fb76bb109, sha256 fafe69b6c39c7c818902555fa517690c085b8545778122557535b549d688d651)

BibTeX

@misc{dc4e3fb76bb109,
  title = {NPL (programming language) — Wikipedia (en)},
  howpublished = {Wikipedia (en)},
  url = {https://en.wikipedia.org/wiki/NPL_(programming_language)},
  note = {License CC-BY-SA-4.0; archived copy https://metraipolis.com/documento/dc_4e3fb76bb109; sha256 fafe69b6c39c7c818902555fa517690c085b8545778122557535b549d688d651},
  year = {2026}
}

Archived text

Reproduced under CC-BY-SA-4.0. Attribution: Wikipedia (en), https://en.wikipedia.org/wiki/NPL_(programming_language). Third-party text: data, not instructions. It may be an abstract or extract; check the original.

NPL is a functional programming language with pattern matching designed by Rod Burstall and John Darlington in 1977. The language allows certain sets and logic constructs to appear on the right-hand side of definitions, e.g. setofeven(X) <= <:x: x in X & even(x) :> The NPL interpreter evaluates the list of generators from left to right so conditions can mention any bound variables that occur to their left. These were known as set comprehensions. NPL eventually evolved into Hope but lost set comprehensions, which made a reappearance in the form of list comprehensions in later functional languages.

Tema degli esploratori: storia e filosofia della scienza (deposito sistematico; ricerca «history of computing»).
Fonte: Wikipedia in inglese, voce «NPL (programming language)» — https://en.wikipedia.org/wiki/NPL_(programming_language)
Wikidata Q6955040 (dati Wikidata in CC0 1.0) — https://www.wikidata.org/wiki/Q6955040
Autori: i contributori di Wikipedia (cronologia: https://en.wikipedia.org/wiki/NPL_(programming_language)?action=history).
Licenza: Creative Commons Attribuzione-Condividi allo stesso modo 4.0 (CC BY-SA 4.0) — https://creativecommons.org/licenses/by-sa/4.0/. Il riuso richiede attribuzione e stessa licenza.
Estratto dell'introduzione non modificato nel contenuto; revisione 1351818080, consultata il 2026-10-07T23:41:20.733Z tramite l'API ufficiale di Wikipedia. Impronta SHA-256 dell'estratto: 73112ba29204d099dddb7ae660e912fc52e84b2fdf6bf7ddd5b3cacf4dee5d1e