Topic       : The GFA-Basic Compendium
Author      : GFA Systemtechnik GmbH
Version     : GFABasic.HYP v2.98 (12/31/2023)
Subject     : Documentation/Programming
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Index Size  : 28056
HCP-Version : 3
Compiled on : Atari
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@hostname   : CAB     
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View Ref-FileINSERT x(i)=y
DELETE x(i)

x: name of an array
i: iexp
y: aexp or sexp, according to variable type of the array

With the instruction INSERT an array element can be inserted. With the
instruction DELETE an array element can be deleted.

INSERT inserts the value of the expression y in the array x() at the position
i. All elements of the array which have an index larger than i are shifted up
one position. Thus if an element stood at position 3 before, then it will be
found at position 4 after the INSERT instruction. The last element of the array
is deleted.

DELETE removes the i-th element of the array x(). All array elements which have
an index larger than i are shifted down one position. The last element of the
array is made zero (or a null string with character string arrays).

These instructions are highly suitable for the management of lists, in which
elements are constantly being inserted or deleted.

Examples:

    DIM x%(5)
    FOR i%=1 TO 5
      x%(i%)=i%
    NEXT i%
    INSERT x%(3)=33
    FOR i%=0 TO 5
      PRINT x%(i%)
    NEXT i%

--> The numbers 0, 1, 2, 33, 3, and 4 are printed on the screen.

    DIM x%(5)
    FOR i%=1 TO 5
      x%(i%)=i%
    NEXT i%
    DELETE x%(3)
    FOR i%=0 TO 5
      PRINT x%(i%)
    NEXT i%

--> The numbers 0, 1, 4, 5, and 0 are printed on the screen.

Memo: This works in the editor but not compiled: INSERT a%(j&)=a%(j&+1)
      Boolean arrays are not supported by these commands.