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--* Subject: swap.as doesn't compile! [/ds13/m/users/edwards/applications/asharp/base/rs3.2/samples/swap.as][A# version 28.I for AIX RS/6000 (debug version)]

--@ Fixed  by: SSD Fri Jul 16 18:34:32 1993
--@ Tested by: swap.as
--@ Summary:   swap.as compiles in v29.2

--> testcomp
--> testrun

#include "aslib.as"

Ag ==> (S: BasicType) -> Aggregate S

-- This function takes two type constructors as arguments
-- and produces a new function to swap aggregate data
-- structure layers.

swap(X:Ag,Y:Ag)(S:BasicType)(x:X Y S):Y X S ==
        [[s for s: S in y]$X(S) for y: Y S in x]$Y(X(S))

-- Now we import those domains we will use.

import List  Integer
import Array Integer
import Integer
import Segment Integer
import String

-- Let's try to swap list and array levels.

al: Array List Integer :=
        array(list(i+j-1 for i in 1..3) for j in 1..3)

print("This is an array of lists: ")()(al)()()

la: List Array Integer := swap(Array,List)(Integer)(al)

print("This is a list of arrays: ")()(la)()