Split the ambivalent system functions into monadic and dyadic pages

compiler-user-guide/docs/introduction/changes-to-behaviour.md

@@ -8,7 +8,7 @@ Thread switching will not occur between lines of code after a function has been
 
 ## Error Trapping
 
-Compiled functions cannot be suspended. Errors occurring within compiled functions are signalled back to the calling environment (in the same way as if [`⎕SIGNAL`](../../../language-reference-guide/system-functions/signal) had been used inside the function).
+Compiled functions cannot be suspended. Errors occurring within compiled functions are signalled back to the calling environment (in the same way as if [`⎕SIGNAL`](../../../language-reference-guide/system-functions/signal-monadic) had been used inside the function).
 
 Similarly, when an error in a compiled function is handled by an Execute trap, the APL expression specified in the trap will be executed in the calling environment and will not be able to see any of the compiled function's local names.
 

dotnet-interface-guide/docs/apl-source-files.md

@@ -183,7 +183,7 @@ This is compiled to a Windows executable (**.exe**) using **make.bat** and run f
 
 ### Defining Namespaces
 
-At least one namespace must be specified in an APL Source file. Namespaces are specified in an APL Source file using the `:Namespace` and `:EndNamespace` statements. Although you can use [`⎕NS`](../../language-reference-guide/system-functions/ns/) and [`⎕CS`](../../language-reference-guide/system-functions/cs/) within functions inside an APL Source file, you should not use these system functions outside function bodies; such use is not prevented, but the results will be unpredictable.
+At least one namespace must be specified in an APL Source file. Namespaces are specified in an APL Source file using the `:Namespace` and `:EndNamespace` statements. Although you can use [`⎕NS`](../../language-reference-guide/system-functions/ns-dyadic/) and [`⎕CS`](../../language-reference-guide/system-functions/cs/) within functions inside an APL Source file, you should not use these system functions outside function bodies; such use is not prevented, but the results will be unpredictable.
 
 `:Namespace Name` introduces a new namespace  relative to the current namespace called `Name`.
 

interface-guide/docs/introduction/concepts.md

@@ -113,10 +113,10 @@ The Dyalog APL GUI is implemented by the following system functions :
 
 |--------------------------------------------------------------|---------------|--------------------------------------------|
 |[`⎕DQ`](../../../language-reference-guide/system-functions/dq)|Dequeue        |processes user actions, invoking callbacks  |
-|[`⎕NQ`](../../../language-reference-guide/system-functions/nq)|Enqueue        |generates an event under program control    |
-|[`⎕WC`](../../../language-reference-guide/system-functions/wc)|Create Object  |creates new object with specified properties|
-|[`⎕WG`](../../../language-reference-guide/system-functions/wg)|Get Properties |gets values of properties from an object    |
-|[`⎕WN`](../../../language-reference-guide/system-functions/wn)|Object Names   |reports names of all children of an object  |
-|[`⎕WS`](../../../language-reference-guide/system-functions/ws)|Set Properties |sets values of properties for an object     |
+|[`⎕NQ`](../../../language-reference-guide/system-functions/nq-monadic)|Enqueue        |generates an event under program control    |
+|[`⎕WC`](../../../language-reference-guide/system-functions/wc-dyadic)|Create Object  |creates new object with specified properties|
+|[`⎕WG`](../../../language-reference-guide/system-functions/wg-dyadic)|Get Properties |gets values of properties from an object    |
+|[`⎕WN`](../../../language-reference-guide/system-functions/wn-monadic)|Object Names   |reports names of all children of an object  |
+|[`⎕WS`](../../../language-reference-guide/system-functions/ws-dyadic)|Set Properties |sets values of properties for an object     |
 
 GUI Objects are a special type of *namespace* and have a name class of 9. They may therefore be managed like any other workspace object. This means that they can be localised in function headers and erased with `⎕EX`. GUI objects are saved with your workspace and reappear when it is loaded or copied.

language-reference-guide/docs/primitive-functions/dyadic-execute.md

@@ -8,8 +8,8 @@ search:
 !!! Warning "Warning"
     If the right argument to _dyadic execute_ could include user input, then there is a risk to data and systems. To reduce this risk, a system function might be more appropriate than the _dyadic execute_ function. For example:
 
-	* use [`⎕VGET`](../system-functions/vget.md) or [`⎕VSET`](../system-functions/vset.md) to get or set the value of one or more variables named within one or more character vectors.
-	* use [`⎕VFI`](../system-functions/vfi.md), [`⎕JSON`](../system-functions/json.md), or [`⎕CSV`](../system-functions/csv.md) to make numbers in text form into actual numbers.
+	* use [`⎕VGET`](../system-functions/vget-monadic.md) or [`⎕VSET`](../system-functions/vset-monadic.md) to get or set the value of one or more variables named within one or more character vectors.
+	* use [`⎕VFI`](../system-functions/vfi-monadic.md), [`⎕JSON`](../system-functions/json-monadic.md), or [`⎕CSV`](../system-functions/csv-monadic.md) to make numbers in text form into actual numbers.
     * use [`⎕OR`](../system-functions/or.md) to call a function by name; exact usage depends on valency. For example, in the namespace with the reference `nsRef`:
       * niladic – `(nsRef.⎕OR fnName)nsRef.{⍺⍺})⍬`
       * monadic – `(nsRef.⎕OR fnName)nsRef.{⍺⍺ ⍵}Y`

language-reference-guide/docs/primitive-functions/execute.md

@@ -8,8 +8,8 @@ search:
 !!! Warning "Warning"
     If the argument to _execute_ could include user input, then there is a risk to data and systems. To reduce this risk, a system function might be more appropriate than the _execute_ function. For example:
 
-	* use [`⎕VGET`](../system-functions/vget.md) or [`⎕VSET`](../system-functions/vset.md) to get or set the value of one or more variables named within one or more character vectors.
-	* use [`⎕VFI`](../system-functions/vfi.md), [`⎕JSON`](../system-functions/json.md), or [`⎕CSV`](../system-functions/csv.md) to make numbers in text form into actual numbers.
+	* use [`⎕VGET`](../system-functions/vget-monadic.md) or [`⎕VSET`](../system-functions/vset-monadic.md) to get or set the value of one or more variables named within one or more character vectors.
+	* use [`⎕VFI`](../system-functions/vfi-monadic.md), [`⎕JSON`](../system-functions/json-monadic.md), or [`⎕CSV`](../system-functions/csv-monadic.md) to make numbers in text form into actual numbers.
     * use [`⎕OR`](../system-functions/or.md) to call a function by name; exact usage depends on valency. For example:
       * niladic – `(⎕OR fnName){⍺⍺}`
       * monadic – `(⎕OR fnName){⍺⍺ ⍵}YY`

language-reference-guide/docs/primitive-operators/i-beam/compiler-control.md

@@ -89,7 +89,7 @@ The result `R` is a multi-line string (that is, a character vector with embedded
 The namespace `N` can contain any or all of following callback functions:
 
 - `N.quadNC` – analogous to the system function [`⎕NC`](../../system-functions/nc.md). When applied monadically to an enclosed character vector it returns the detailed nameclass of that name. For example, given the name of a global dfn it returns the value `3.2`.
-- `N.quadAT` – analogous to the system function [`⎕AT`](../../system-functions/at.md). When applied monadically to an enclosed character vector it returns a 1 by 4 matrix whose first item is a vector of 3 integers describing (respectively) the result, function valence, and operator valence of the name.
+- `N.quadAT` – analogous to the system function [`⎕AT`](../../system-functions/at-monadic.md). When applied monadically to an enclosed character vector it returns a 1 by 4 matrix whose first item is a vector of 3 integers describing (respectively) the result, function valence, and operator valence of the name.
 - `N.getValue` – used to obtain the name of a global constant. When applied monadically to a character vector that is a global constant it returns the enclose of the constant value, otherwise it returns `⍬`.
 
 Each of these callback functions returns information about names that should be guaranteed to exist when the compiled functions are executed. The compiler assumes that the information returned by the callbacks is correct, and generates bytecode accordingly. In the case of `quadNC` and `quadAT`, if the information returned by the callbacks turns out not to be correct when the compiled function is executed, then a runtime error is generated.

language-reference-guide/docs/primitive-operators/i-beam/disable-component-checksum-validation.md

@@ -6,7 +6,7 @@ search:
 
 # <span>Disable Component Checksum Validation</span> `{R}←3002⌶Y`{{key}}
 
-Checksums allow component files to be validated and repaired using [`⎕FCHK`](../../system-functions/fchk.md).
+Checksums allow component files to be validated and repaired using [`⎕FCHK`](../../system-functions/fchk-monadic.md).
 
 From Version 13.1 onwards, components which contain checksums are also validated on every component read.
 

language-reference-guide/docs/primitive-operators/i-beam/json-translate-name.md

@@ -36,7 +36,7 @@ foo
 
 ```
 
-For further details, see [JSON Name Mangling](../../system-functions/json.md).
+For further details, see [JSON Name Mangling](../../system-functions/json-monadic.md).
 
 <!-- Hidden search keywords -->
 <div style="display: none;">

language-reference-guide/docs/primitive-operators/i-beam/list-loaded-files.md

@@ -20,7 +20,7 @@ The editor may be used to edit Dyalog script files (*.dyalog* files) and general
 |4      |Newline  |
 |5      |Flags    |
 
-Encoding, newline and flags are defined the same as for `⎕NGET`. See [File Encodings](../../system-functions/nget.md). Checksum is an 8-character hexadecimal value, see [GetBuildID](../../../../object-reference/methodorevents/getbuildid)  for more information.
+Encoding, newline and flags are defined the same as for `⎕NGET`. See [File Encodings](../../system-functions/nget-dyadic.md). Checksum is an 8-character hexadecimal value, see [GetBuildID](../../../../object-reference/methodorevents/getbuildid)  for more information.
 
 <h2 class="example">Examples</h2>
 ```apl

language-reference-guide/docs/primitive-operators/i-beam/list-shared-code-files-attached-names.md

@@ -29,7 +29,7 @@ The rows of the matrix (one row for each shared code file) are ordered to corres
 
 Lists the names in the shared code file identified by the specified memory address.
 
-`Y` is an integer vector that would be a valid right argument to [`⎕NL`](../../../system-functions/nl/); it identifies the nameclasses and subclasses for which the names should be listed.
+`Y` is an integer vector that would be a valid right argument to [`⎕NL`](../../../system-functions/nl-monadic/); it identifies the nameclasses and subclasses for which the names should be listed.
 
 `X` is the slot identifier (an integer in the range 1-8) for the unique fixed virtual memory address of the shared code file.
 

language-reference-guide/docs/primitive-operators/i-beam/update-function-time-and-user-stamp.md

@@ -6,7 +6,7 @@ search:
 
 # <span>Update Function Time and User Stamp</span> `{R}←X(1159⌶)Y`{{key}}
 
-`Y` is an array of function names in the same format as the right argument of `⎕AT`. For further information, see [Attributes](../../system-functions/at.md).
+`Y` is an array of function names in the same format as the right argument of `⎕AT`. For further information, see [Attributes](../../system-functions/at-monadic.md).
 
 `X` is an array of function attributes in the same format as the output of `⎕AT`.
 

language-reference-guide/docs/system-commands/objects.md

@@ -2,7 +2,7 @@
 
 # <span>List Global Namespaces</span> `)OBJECTS {nm}`
 
-This command displays the names of global **namespaces** in the active workspace.  Names are displayed in the [`AV`](../system-functions/av.md) collating order.  If a name is included after the command, only those names starting at or after the given name in collating order are displayed.  Namespaces are objects created using [`⎕NS`](../system-functions/ns.md), [`)NS`](ns.md) or [`⎕WC`](../system-functions/wc.md) and have name class 9.
+This command displays the names of global **namespaces** in the active workspace.  Names are displayed in the [`AV`](../system-functions/av.md) collating order.  If a name is included after the command, only those names starting at or after the given name in collating order are displayed.  Namespaces are objects created using [`⎕NS`](../system-functions/ns-dyadic.md), [`)NS`](ns.md) or [`⎕WC`](../system-functions/wc-dyadic.md) and have name class 9.
 
 Note:  [`)OBS`](obs.md) can be used as an **alternative** to `)OBJECTS`
 

language-reference-guide/docs/system-functions/at-disambiguation.md

@@ -0,0 +1,22 @@
+---
+search:
+  exclude: true
+---
+
+# <span>Attributes</span> `⎕AT`
+
+## Monadic `⎕AT` means
+
+[Object Attributes](at-monadic.md)
+```apl
+      ⎕AT 'plus'
+ 1 1 0  2026 7 30 15 20 38 0  0  Pete 
+```
+
+## Dyadic `⎕AT` means
+
+[Object Attributes for APL2](at-dyadic.md)
+```apl
+      1 ⎕AT 'plus'
+1 1 0
+```

language-reference-guide/docs/system-functions/at-dyadic.md

@@ -0,0 +1,90 @@
+---
+search:
+  boost: 2
+---
+
+# <span>Object Attributes for APL2</span> `R←X ⎕AT Y`{{key}}
+
+`Y` can be a simple character scalar, vector or matrix, or a vector of character vectors representing the names of 0 or more defined functions or operators. This function closely emulates the APL2 implementation; for the form that returns information more appropriate to Dyalog APL, see [Object Attributes](at-monadic.md).
+
+`Y` specifies one or more names. If `Y` specifies a single name as a character scalar, a character vector, or as a scalar enclosed character vector, the result `R` is a vector. If `Y` specifies one or more names as a character matrix or as a vector of character vectors `R` is a matrix with one row per name in `Y`.
+
+It returns the same rank and shape result containing information that matches the APL2 implementation as closely as possible.
+
+The number of elements or columns in `R` and their meaning depends upon the value of `X` which may be 1, 2, 3 or 4.
+
+If `X` is 1, `R` specifies _valences_ and contains 3 elements (or columns) whose meaning is as follows:
+
+|---|----------------|---------------------------------------------------------------------------------------------------------------------------------------|
+|1 |Explicit result |1 if the object has an explicit result or is a variable 0 otherwise |
+|2 |Function valence|0 if the object is a niladic function or not a function 1 if the object is a monadic function 2 if the object is an ambivalent function|
+|3 |Operator valence|0 if the object is not an operator 1 if the object is a monadic operator 2 if the object is a dyadic operator |
+
+<h4 class="example">Examples</h4>
+
+The following values correspond to the syntax shown alongside:
+
+|-----|--------|
+| `0 0 0` | `∇ FOO` |
+| `1 0 0` | `∇ Z←FOO` |
+| `1 0 0` | `∇ {Z}←FOO` |
+| `0 2 0` | `∇ {A} FOO B` |
+| `1 1 2` | `∇ {Z}←(F OP G)B` |
+
+If `X` is 2, `R` specifies _fix times_ (the time the object was last updated) for functions and operators named in `Y`. The time is reported as 7 integer elements (or columns) in the same form as `⎕TS`, whose meaning is as follows. The fix time reported for names in `Y` which are not defined functions or operators is 0.
+
+|---|-------------------------------------------|
+|1 |Year |
+|2 |Month |
+|3 |Day |
+|4 |Hour |
+|5 |Minute |
+|6 |Second |
+|7 |Milliseconds (this is always reported as 0)|
+
+If `X` is 3, `R` specifies _execution properties_ and contains 4 elements (or columns) whose meaning is as follows:
+
+|---|------------------------|---------------------------------------------------------------------------------------|
+|1 |Displayable |0 if the object is displayable 1 if the object is not displayable |
+|2 |Suspendable |0 if execution will suspend in the object 1 if execution will not suspend in the object|
+|3 |Weak Interrupt behaviour|0 if the object responds to interrupt 1 if the object ignores interrupt |
+|4 |&nbsp; |(always 0) |
+
+If `X` is 4, `R` specifies _object size_ and contains 2 elements (or columns) that both report the `⎕SIZE` of the object.
+
+<h2 class="example">Examples</h2>
+
+```apl
+    ∇ {z}←{l}(fn myop)r
+
+[1] ...
+
+    ∇ z←foo
+
+[1] ...
+
+    ∇ z←{larg}util rarg
+
+[1] ...
+
+      ⎕LOCK'foo'
+
+      util2←util
+
+      1 ⎕AT 'myop' 'foo' 'util' 'util2'
+1 2 1
+1 0 0
+1 2 0
+1 2 0
+
+      2 ⎕AT'myop' 'foo' 'util' 'util2'
+1996 8  2  2 13 56 0
+   0 0  0  0  0  0 0
+1996 3  1 14 12 10 0
+1998 8 26 16 16 42 0
+```
+
+<!-- Hidden search keywords -->
+<div style="display: none;">
+  ⎕AT
+</div>