Language Features

At the moment, the following sections describe only those language features that are New or Enhanced relative to the Extended APL Standard, or that deserve special comment.

Syntax

• Strand Assignment: (A₁ A₂ ... A_n)←R
• Modify Assignment: Af←R
• Modify Strand Assignment: (A₁ A₂ ... A_n)f←R
• Function/Operator Assignment: A←f, A←op1, A←op2
• Sink: ←A
• Comment Marker: ⍝

Primitive functions

• Index Generator: ⍳R
• Index Of: L⍳R
• Indexing: R[L], R[L]←A, R[L]f←A, L⌷R, L⊃R
• Matrix Inverse/Divide: ⌹R, L⌹R
• Without: L~R

Primitive operators

• Axis: f[X], f op1[X], f op2[X]g
• Composition: f∘g, f∘R, L∘g
• Null: f⊙
• Rank: f⍤X
• Rank with Axis: f⍥[X]

Datatypes

• Infinity: ∞ and ¯∞
• Arithmetic Progression Arrays: 2 3 4⍴⍳24
• Unicode Characters

System Functions

• ⎕AF (Atomic Function) Synonymous with ⎕UCS
• ⎕CR (Canonical Representation)
• ⎕DM (Diagnostic Message)
• ⎕DR (Data Representation)
• ⎕ERROR (Error Signal)
• ⎕SIZE (Object Size)
• ⎕SYSID (System Identifier)
• ⎕SYSVER (System Version)
• ⎕TC/⎕TCxxx (Terminal Control)
• ⎕TYPE (Prototype)
• ⎕UCS (Universal Character Set)

System Variables

• Scalar System Variables (⎕CT, ⎕IO, ⎕PP, ⎕PW, ⎕RL)
• ⎕FC (Format Control)
• ⎕IC (Indeterminate Control)