Migration level: Difference between revisions

From APL Wiki
Jump to navigation Jump to search
m (Text replacement - "http://help.dyalog.com" to "https://help.dyalog.com")
No edit summary
Line 1: Line 1:
{{Built-ins|Migration level|⎕ML|⎕EL}} or '''Evolution level''' is a number that, in [[Dyalog APL]] and [[APL+Win]] respectively, determines exact where the original [[NARS]] specification and the current [[APL2]] implementation differ. A lower value represents a behaviour closer to NARS, while a higher the value represents a behaviour closer to APL2.
{{Built-ins3|Migration level|⎕ML|⎕EL|⎕CS}}, '''Evolution level''', or '''Compatibility setting''' is a number that, in [[Dyalog APL]], [[APL+Win]], and [[APLX]] respectively, specifies exact behaviour relative to [[APL2]]. In Dyalog APL and APL+Win, a lower value represents a behaviour closer to the original [[NARS]] specification, while a higher the value represents a behaviour closer to APL2. In APLX, a lower value matches APL2 while a higher value indicates higher [[backwards compatibility]] with [[APL.68000]].


== APL+Win settings ==
== APL+Win settings ==
Line 65: Line 65:
|}
|}
Alternatively, the definitions can be used directly inside the text substitutions, whereby one avoids polluting existing code with these cover names.
Alternatively, the definitions can be used directly inside the text substitutions, whereby one avoids polluting existing code with these cover names.
== APLX settings ==
APLX treats the value as a collection of individual bits, thus allowing the combination of an exact set of behaviours:
{|class=wikitable
| <source lang=apl inline>⎕CS←1</source> || [[Strand notation|Stranding]] is done before [[bracket indexing]]
|-
| <source lang=apl inline>⎕CS←2</source> || The [[name class]] of an invalid name is 4 rather than ¯1.
|-
| <source lang=apl inline>⎕CS←4</source> || Format (<source lang=apl inline>⍕</source>) and default output uses the same width for all columns, rather than determining  the  width separately for  each column.
|}


== External links ==
== External links ==
Line 71: Line 83:


* [https://help.dyalog.com/latest/#Language/System%20Functions/ml.htm Dyalog]
* [https://help.dyalog.com/latest/#Language/System%20Functions/ml.htm Dyalog]
* [http://microapl.com/apl_help/ch_020_070_140.htm APLX]


{{APL built-ins}}[[Category:System constants]]
{{APL built-ins}}[[Category:System constants]]

Revision as of 08:43, 8 February 2021

⎕ML ⎕EL ⎕CS

Migration level (⎕ML, ⎕EL, ⎕CS), Evolution level, or Compatibility setting is a number that, in Dyalog APL, APL+Win, and APLX respectively, specifies exact behaviour relative to APL2. In Dyalog APL and APL+Win, a lower value represents a behaviour closer to the original NARS specification, while a higher the value represents a behaviour closer to APL2. In APLX, a lower value matches APL2 while a higher value indicates higher backwards compatibility with APL.68000.

APL+Win settings

[TBD]

Dyalog settings

Dyalog APL currently offers the following settings:

⎕ML=0 Z←∊R Monadic ∊ is interpreted as Type rather than Enlist.
⎕ML=1 Default behaviour
⎕ML≤2 Z←↑R Monadic ↑ is interpreted as First rather than Mix.
Z←⊃R Monadic ⊃ is interpreted as Mix rather than First.
Z←≡R Monadic ≡ returns a positive rather than a negative value, if its argument has non-uniform depth.
⎕ML=3 R←X⊂[K]Y Dyadic ⊂ is interpreted as Partition (⊆) rather than Partitioned Enclose.
⎕TC The order of the elements of ⎕TC is the same as in APL2.

Work-arounds

When migrating to Dyalog APL, the below drop-ins for the affected built-ins allow setting ⎕ML←1 while preserving code behaviour. It is then safe to programmatically (as shown in the rightmost column) change all occurrences of the affected built-ins with their respective covers.

Migrating from Define Then run this on all code
⎕ML=0 
Epsilon←{×⎕NC'⍺':⍺∊⍵ ⋄ ⊃0⍴⊂⍵}
 '''[^'']+''' '∊'⎕R'&' 'Epsilon'
⎕ML=2 
UpArrow←{×⎕NC'⍺':⍺↑⍵ ⋄ ⊃⍵}
RightShoe←{×⎕NC'⍺':⍺↑⍵ ⋄ ↑⍵}
EqualUnderbar←|≡
 '''[^'']+''' '↑' '⊃' '≡'⎕R'&' 'UpArrow' 'RightShoe' 'EqualUnderbar'
⎕ML=3 
UpArrow←{×⎕NC'⍺':⍺↑⍵ ⋄ ⊃⍵}
RightShoe←{×⎕NC'⍺':⍺↑⍵ ⋄ ↑⍵}
EqualUnderbar←(|≡)
LeftShoe←{×⎕NC'⍺':⍺⊆⍵ ⋄ ⊂⍵}
quadTC←(⎕UCS 8 13 10)
 '''[^'']+''' '↑' '⊃' '≡' '⊂' '⎕TC'⎕R'&' 'UpArrow' 'RightShoe' 'EqualUnderbar' 'LeftShoe' ' quadTC'

Alternatively, the definitions can be used directly inside the text substitutions, whereby one avoids polluting existing code with these cover names.

APLX settings

APLX treats the value as a collection of individual bits, thus allowing the combination of an exact set of behaviours:

⎕CS←1 Stranding is done before bracket indexing
⎕CS←2 The name class of an invalid name is 4 rather than ¯1.
⎕CS←4 Format (⍕) and default output uses the same width for all columns, rather than determining the width separately for each column.

External links

Documentation


APL built-ins [edit]
Primitives (Timeline) Functions
Scalar
Monadic Conjugate ∙ Negate ∙ Signum ∙ Reciprocal ∙ Magnitude ∙ Exponential ∙ Natural Logarithm ∙ Floor ∙ Ceiling ∙ Factorial ∙ Not ∙ Pi Times ∙ Roll ∙ Type ∙ Imaginary ∙ Square Root ∙ Round
Dyadic Add ∙ Subtract ∙ Times ∙ Divide ∙ Residue ∙ Power ∙ Logarithm ∙ Minimum ∙ Maximum ∙ Binomial ∙ Comparison functions ∙ Boolean functions (And, Or, Nand, Nor) ∙ GCD ∙ LCM ∙ Circular ∙ Complex ∙ Root
Non-Scalar
Structural Shape ∙ Reshape ∙ Tally ∙ Depth ∙ Ravel ∙ Enlist ∙ Table ∙ Catenate ∙ Reverse ∙ Rotate ∙ Transpose ∙ Raze ∙ Mix ∙ Split ∙ Enclose ∙ Nest ∙ Cut (K) ∙ Pair ∙ Link ∙ Partitioned Enclose ∙ Partition
Selection First ∙ Pick ∙ Take ∙ Drop ∙ Unique ∙ Identity ∙ Stop ∙ Select ∙ Replicate ∙ Expand ∙ Set functions (Intersection ∙ Union ∙ Without) ∙ Bracket indexing ∙ Index ∙ Cartesian Product ∙ Sort
Selector Index generator ∙ Grade ∙ Index Of ∙ Interval Index ∙ Indices ∙ Deal ∙ Prefix and suffix vectors
Computational Match ∙ Not Match ∙ Membership ∙ Find ∙ Nub Sieve ∙ Encode ∙ Decode ∙ Matrix Inverse ∙ Matrix Divide ∙ Format ∙ Execute ∙ Materialise ∙ Range
Operators Monadic Each ∙ Commute ∙ Constant ∙ Replicate ∙ Expand ∙ Reduce ∙ Windowed Reduce ∙ Scan ∙ Outer Product ∙ Key ∙ I-Beam ∙ Spawn ∙ Function axis ∙ Identity (Null, Ident)
Dyadic Bind ∙ Compositions (Compose, Reverse Compose, Beside, Withe, Atop, Over) ∙ Inner Product ∙ Determinant ∙ Power ∙ At ∙ Under ∙ Rank ∙ Depth ∙ Variant ∙ Stencil ∙ Cut ∙ Direct definition (operator) ∙ Identity (Lev, Dex)
Quad names Index origin ∙ Comparison tolerance ∙ Migration level ∙ Atomic vector
Retrieved from ‘https://aplwiki.com/index.php?title=Migration_level&oldid=6310’