MathAction SandBoxLexicalScope

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SandboxFreeAndLocal

j is referenced out of scope

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for i in 1..5 repeat
        j:Integer := i^2
        output(i::OutputForm)$OutputPackage

   1
   2
   3
   4
   5

Type: Void

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output(j::OutputForm)$OutputPackage

   25

Type: Void

The code above returns an error in OpenAxiom 1.2.0 (Revision >= 563).

It sould be written like this:

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j: Integer

Type: Void

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for i in 1..5 repeat
        j := i^2
        output(i::OutputForm)$OutputPackage

   1
   2
   3
   4
   5

Type: Void

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output(j::OutputForm)$OutputPackage

   25

Type: Void

Oddly, using j out of scope is also allowed in Aldor:

aldor

#pile
#include "axiom"

import from PositiveInteger

CheckScope1(): with
    checkscope1: () -> PositiveInteger
  == add
    checkscope1():PositiveInteger ==
      for i in 1..5 repeat
        j:PositiveInteger := i^2
        --output(i::OutputForm)$OutputPackage
      --output(j::OutputForm)$OutputPackage
      j

aldor

   Compiling FriCAS source code from file 
      /var/lib/zope2.10/instance/axiom-wiki/var/LatexWiki/8452782754204589047-25px003.as
      using Aldor compiler and options 
-O -Fasy -Fao -Flsp -lfricas -Mno-ALDOR_W_WillObsolete -DFriCAS -Y $FRICAS/algebra -I $FRICAS/algebra
      Use the system command )set compiler args to change these 
      options.
   The )library system command was not called after compilation.

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checkscope1()

   There are no library operations named checkscope1 
      Use HyperDoc Browse or issue
                            )what op checkscope1
      to learn if there is any operation containing " checkscope1 " in 
      its name.

   Cannot find a no-argument definition or library operation named 
      checkscope1 .

aldor

#pile
#include "axiom"

import from PositiveInteger

CheckScope2(): with
    checkscope2: () -> PositiveInteger
  == add
    checkscope2():PositiveInteger ==
      local j:PositiveInteger
      for i in 1..5 repeat
        j := i^2
        --output(i::OutputForm)
        --output(j::OutputForm)$OutputPackage
      j

aldor

   Compiling FriCAS source code from file 
      /var/lib/zope2.10/instance/axiom-wiki/var/LatexWiki/8264748852590484820-25px005.as
      using Aldor compiler and options 
-O -Fasy -Fao -Flsp -lfricas -Mno-ALDOR_W_WillObsolete -DFriCAS -Y $FRICAS/algebra -I $FRICAS/algebra
      Use the system command )set compiler args to change these 
      options.
   The )library system command was not called after compilation.

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checkscope2()

   There are no library operations named checkscope2 
      Use HyperDoc Browse or issue
                            )what op checkscope2
      to learn if there is any operation containing " checkscope2 " in 
      its name.

   Cannot find a no-argument definition or library operation named 
      checkscope2 .

Ralf Hemmecke wrote:

Ooops, what in would be illegal? I just had to replace (as I said) the braces by parentheses, since parens are used to group sequences of commands. (Same as braces in Aldor.)

spad

)abbrev domain AAA Aaa
Aaa: with
    bar: Integer -> Integer
  == add
    (x: Integer := 4; y: Integer := 3)
    bar(a: Integer): Integer == x + a + z
    z: Integer := 3 + y

spad

   Compiling FriCAS source code from file 
      /var/lib/zope2.10/instance/axiom-wiki/var/LatexWiki/2292316700013189339-25px007.spad
      using old system compiler.
   AAA abbreviates domain Aaa 
------------------------------------------------------------------------
   initializing NRLIB AAA for Aaa 
   compiling into NRLIB AAA 
   compiling exported bar : Integer -> Integer
****** comp fails at level 2 with expression: ******
error in function bar 

(+ (+ |x| |a|) | << z >> |)
****** level 2  ******
$x:= z
$m:= $EmptyMode
$f:=
((((|a| # #) (|y| # #) (|x| # #) (* #) ...)))

   >> Apparent user error:
   cannot compile (+ (+ x a) z)

Bill Page wrote:

But this works since z is now in "scope" of the function body of bar.

spad

)abbrev domain AAA Aaa
Aaa: with
    bar: Integer -> Integer
  == add
    (x: Integer := 4; y: Integer := 3)
    z: Integer
    bar(a: Integer): Integer == x + a + z
    z: Integer := 3 + y

spad

   Compiling FriCAS source code from file 
      /var/lib/zope2.10/instance/axiom-wiki/var/LatexWiki/6187271087318241578-25px008.spad
      using old system compiler.
   AAA abbreviates domain Aaa 
------------------------------------------------------------------------
   initializing NRLIB AAA for Aaa 
   compiling into NRLIB AAA 
   compiling exported bar : Integer -> Integer
Time: 0 SEC.

(time taken in buildFunctor:  0)

;;;     ***       |Aaa| REDEFINED

;;;     ***       |Aaa| REDEFINED
Time: 0 SEC.

   Warnings: 
      [1] bar:  z has no value

   Cumulative Statistics for Constructor Aaa
      Time: 0 seconds

   finalizing NRLIB AAA 
   Processing Aaa for Browser database:
--->-->Aaa(constructor): Not documented!!!!
--->-->Aaa((bar ((Integer) (Integer)))): Not documented!!!!
--->-->Aaa(): Missing Description
; compiling file "/var/aw/var/LatexWiki/AAA.NRLIB/AAA.lsp" (written 04 APR 2022 06:56:44 PM):

; /var/aw/var/LatexWiki/AAA.NRLIB/AAA.fasl written
; compilation finished in 0:00:00.014
------------------------------------------------------------------------
   Aaa is now explicitly exposed in frame initial 
   Aaa will be automatically loaded when needed from 
      /var/aw/var/LatexWiki/AAA.NRLIB/AAA

An example of Union for branches of if that yield different types:

spad

)abbrev domain BBB Bbb
Bbb: with
    foo: Integer -> Union(Integer,Float)
  == add
    foo(a: Integer): Union(Integer,Float) ==
     x:Union(Integer,Float)
     if a>0 then
         x := 1
     else
         x := 2.3

     if x case Integer then x:=x*x
     else x:=x*x
     x

spad

   Compiling FriCAS source code from file 
      /var/lib/zope2.10/instance/axiom-wiki/var/LatexWiki/1133161573775318814-25px009.spad
      using old system compiler.
   BBB abbreviates domain Bbb 
------------------------------------------------------------------------
   initializing NRLIB BBB for Bbb 
   compiling into NRLIB BBB 
   compiling exported foo : Integer -> Union(Integer,Float)
Time: 0.01 SEC.

(time taken in buildFunctor:  0)

;;;     ***       |Bbb| REDEFINED

;;;     ***       |Bbb| REDEFINED
Time: 0 SEC.

   Cumulative Statistics for Constructor Bbb
      Time: 0.01 seconds

   finalizing NRLIB BBB 
   Processing Bbb for Browser database:
--->-->Bbb(constructor): Not documented!!!!
--->-->Bbb((foo ((Union (Integer) (Float)) (Integer)))): Not documented!!!!
--->-->Bbb(): Missing Description
; compiling file "/var/aw/var/LatexWiki/BBB.NRLIB/BBB.lsp" (written 04 APR 2022 06:56:44 PM):

; /var/aw/var/LatexWiki/BBB.NRLIB/BBB.fasl written
; compilation finished in 0:00:00.009
------------------------------------------------------------------------
   Bbb is now explicitly exposed in frame initial 
   Bbb will be automatically loaded when needed from 
      /var/aw/var/LatexWiki/BBB.NRLIB/BBB

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foo(0)

$\label{eq1}5.29$

(1)

Type: Union(Float,...)

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foo(1)

$\label{eq2}1$

(2)

Type: Union(Integer,...)

*Gaby wrote:

Try:

spad

)abbrev package BILLPAGE BillPageUnion
BillPageUnion(): Public == Private where
 Public ==> with
   foo: (Integer,Integer) -> Union(Integer,Float)
 Private ==> add
   makeU(i:Integer): Union(Integer,Float) ==
     even? i => 1
     3.14

   foo(i:Integer,j:Integer):Union(Integer,Float) ==
     x: Union(Integer,Float) := makeU(i)
     y: Union(Integer,Float) := makeU(i)
     if x case Integer then
       xf:=x::Integer::Float
       if y case Integer then
         xf ^ y
       else
         xf ^ y
     else
       if y case Integer then
         x ^ y
       else
         x ^ y

spad

   Compiling FriCAS source code from file 
      /var/lib/zope2.10/instance/axiom-wiki/var/LatexWiki/7820214535587786138-25px011.spad
      using old system compiler.
   BILLPAGE abbreviates package BillPageUnion 
------------------------------------------------------------------------
   initializing NRLIB BILLPAGE for BillPageUnion 
   compiling into NRLIB BILLPAGE 
   compiling local makeU : Integer -> Union(Integer,Float)
Time: 0.01 SEC.

   compiling exported foo : (Integer,Integer) -> Union(Integer,Float)
Time: 0 SEC.

(time taken in buildFunctor:  0)

;;;     ***       |BillPageUnion| REDEFINED

;;;     ***       |BillPageUnion| REDEFINED
Time: 0 SEC.

   Cumulative Statistics for Constructor BillPageUnion
      Time: 0.01 seconds

   finalizing NRLIB BILLPAGE 
   Processing BillPageUnion for Browser database:
--->-->BillPageUnion(constructor): Not documented!!!!
--->-->BillPageUnion((foo ((Union (Integer) (Float)) (Integer) (Integer)))): Not documented!!!!
--->-->BillPageUnion(): Missing Description
; compiling file "/var/aw/var/LatexWiki/BILLPAGE.NRLIB/BILLPAGE.lsp" (written 04 APR 2022 06:56:44 PM):

; /var/aw/var/LatexWiki/BILLPAGE.NRLIB/BILLPAGE.fasl written
; compilation finished in 0:00:00.014
------------------------------------------------------------------------
   BillPageUnion is now explicitly exposed in frame initial 
   BillPageUnion will be automatically loaded when needed from 
      /var/aw/var/LatexWiki/BILLPAGE.NRLIB/BILLPAGE

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