Editing Vacuous truth (section)

== In computer programming ==
Many programming environments have a mechanism for querying if every item in a collection of items satisfies some predicate.  It is common for such a query to always evaluate as true for an empty collection.  For example:

* In [[JavaScript]], the [[array]] method <code>every</code> executes a provided callback function once for each element present in the array, only stopping (if and when) it finds an element where the callback function returns false. Notably, calling the <code>every</code> method on an empty array will return true for any condition.<ref>{{Cite web|url=https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/every|title=Array.prototype.every() - JavaScript &#124; MDN|website=developer.mozilla.org|date=27 November 2023 }}</ref>
* In [[Python (Programming Language)|Python]], the built in <code>all()</code> function returns <code>True</code> only when all of the elements of an array are <code>True</code> or the array is of length zero as shown in these examples: <code>all([1,1])==True; all([1,1,0])==False; all([])==True</code>.<ref>{{cite web |title=Built-in Functions – Python 3.10.2 documentation |url=https://docs.python.org/3/library/functions.html#all |website=docs.python.org}}</ref> A less ambiguous way to express this is to say <code>all()</code> returns True when '''none of the elements are False'''.
* In [[Rust (programming language)|Rust]], the <code>Iterator::all</code> function accepts an iterator and a predicate and returns <code>true</code> only when the predicate returns <code>true</code> for all items produced by the iterator, or if the iterator produces no items.<ref>{{Cite web|url=https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.all|title=Iterator in std::iter – Rust|website=doc.rust-lang.org}}</ref>
* In SQL, the function, the function <code>ANY_VALUE</code> can differ depending on the RDBMS's behaviour relating [[Null (SQL)|NULLs]] to vacuous truth. Some RDBMS might return <code>null</code> even if there are non-<code>null</code> values.<ref>{{Cite web |title=The ANY_VALUE(…) Aggregate Function |url=https://modern-sql.com/caniuse/any_value |access-date=2024-11-27 |website=modern-sql.com |language=en}}</ref> Some DBMS might not allow for its use in <code>filter(…)</code> or <code>over(…)</code> clauses.
* In [[Kotlin (programming language)|Kotlin]], the collection method <code>all</code> returns <code>true</code> when the collection is empty.
* In [[C Sharp (programming language)|C#]], the Linq method <code>All</code> returns <code>true</code> when the collection is empty.
* In [[C++]], the <code>std::all_of</code> function template returns <code>true</code> for an empty collection.<ref>{{Cite web |date=19 March 2024 |title=std::all_of, std::any_of, std::none_of |url=https://en.cppreference.com/w/cpp/algorithm/all_any_none_of |url-status=live |archive-url=https://web.archive.org/web/20241201074645/https://en.cppreference.com/w/cpp/algorithm/all_any_none_of |archive-date=1 December 2024 |access-date=9 December 2024 |website=Cpprefeference}}</ref>