Pair: Difference between revisions

{{Built-in|Pair|⍮}} or '''Juxtapose''' is a [[primitive function]] equivalent to the [[dfn]] <syntaxhighlight lang=apl inline>{⍺←,⊂ ⋄ ⍺ ⍵}</syntaxhighlight> which aids in constructing nested arrays during [[tacit programming]] where [[stranding]] by juxtaposition is not available. It is also equivalent to the [[catenate|catenation]] of the [[enclose]]d arguments; <syntaxhighlight lang=apl inline>,⍥⊂</syntaxhighlight> using the [[Over]] [[operator]]<ref>[https://www.jsoftware.com/papers/satn41.htm "Composition and Enclosure"] §

Composition Operators. SATN-41, 1981-06-20.</ref> or <syntaxhighlight lang=apl inline>,⍨∘⊂⍨∘⊂</syntaxhighlight> using only the traditional operators [[Commute]] and [[Compose]]. It was introduced in [[Extended Dyalog APL]], and then adopted into [[dzaima/APL]]. It was added to [[BQN]] with the glyph <code>⋈</code> in 2021.