EXPAND
|
dynamic-clause | [GIVING
operand5]
|
||
array-clause |
This document covers the following topics:
For an explanation of the symbols used in the syntax diagram, see Syntax Symbols.
Related statements: REDUCE
| RESIZE
Belongs to Function Group: Memory Management Control for Dynamic Variables or X-Arrays
The EXPAND
statement is used to expand:
the allocated length of a dynamic variable
(dynamic-clause
), or
the number of occurrences of X-arrays
(array-clause
).
For further information, see the following sections in the Programming Guide:
Allocating/Freeing Memory Space for a Dynamic Variable
Storage Management of X-Group Arrays
Operand Definition Table:
Operand | Possible Structure | Possible Formats | Referencing Permitted | Dynamic Definition | |||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
operand1
|
S | A | A | U | B | no | no | ||||||||||||||
operand2
|
C | S | I | no | no | ||||||||||||||||
operand3
|
A | G | A | U | N | P | I | F | B | D | T | L | C | G | O | yes | no | ||||
operand4
|
C | S | N | P | I | no | no | ||||||||||||||
operand5
|
S | I4 | no | yes |
Syntax Element Description:
Syntax Element | Description |
---|---|
dynamic-clause
|
Dynamic
Clause:
The |
operand1
|
Dynamic Variable:
|
operand2
|
Target Length of Dynamic Variable:
|
array-clause
|
Array Clause:
The |
operand3
|
X-Array:
|
dim
|
Dimension:
The lower and upper bound notation
( |
GIVING
operand5
|
GIVING Clause:
If the If the |
[SIZE OF ] DYNAMIC [ VARIABLE ] operand1
TO operand2
|
The EXPAND DYNAMIC VARIABLE
statement expands the
allocated size of a dynamic variable (operand1) to
the value specified with operand2
.
If operand2
is less than the
currently allocated length of operand1
,
the statement will be ignored for this dynamic variable. The currently
allocated length (*LENGTH
)
of the dynamic variable is not modified.
[AND RESET [OCCURRENCES OF ] ARRAY
operand3 TO
(dim[,dim
[,dim]])]
|
The EXPAND ARRAY
statement increases the number of
occurrences of the X-array
(operand3
) to the upper and lower bound
specified with TO
(dim
[,dim[,dim]])
.
The RESET
option resets all occurrences of the resized
X-array to its default zero value. By default (no RESET
option),
the actual values are kept and the resized (new) occurrences are reset.
When using the EXPAND
statement, it is only possible to
increase the number of occurrences. If the requested number is smaller than the
currently allocated number of occurrences, it will simply be ignored.
An upper or lower bound used in an EXPAND
statement must
be exactly the same as the corresponding upper or lower bound defined for the
array.
Example:
DEFINE DATA LOCAL 1 #a(I4/1:*) 1 #g(1:*) 2 #ga(I4/1:*) 1 #i(i4) END-DEFINE ... /* allocating #a(1:10) EXPAND ARRAY #a TO (1:10) /* #a is allocated 10 EXPAND ARRAY #a TO (*:10) /* occurrences. /* allocating #ga(1:10,1:20) EXPAND ARRAY #g TO (1:10) /* 1st dimension is set to (1:10) EXPAND ARRAY #ga TO (*:*,1:20) /* 1st dimension is dependent and /* therefore kept with (*:*) /* 2nd dimension is set to (1:20) EXPAND ARRAY #a TO (5:10) /* This is rejected because the lower index /* must be 1 or * EXPAND ARRAY #a TO (#i:10) /* This is rejected because the lower index /* must be 1 or * EXPAND ARRAY #ga TO (1:10,1:20) /* (1:10) for the 1st dimension is rejected /* because the dimension is dependent and /* must be specified with (*:*).
For further information, see the following topics in the Programming Guide:
Each of the dimensions (dim) specified in the Array Clause is defined using the following syntax:
operand4 | :
|
operand4 | ||||
* | * |
The lower and upper bound notation
(operand4
or asterisk) to which the
X-array should be expanded
is specified here. If the current value of the upper or lower bound should be
used, an asterisk (*) may be specified in place of
operand4
. Instead of *:*
,
you may also specify a single asterisk.
The number of dimensions (dim
) must exactly match the
defined number of dimensions of the X-array (1, 2 or 3).
If the number of occurrences for a specified dimension is less than the number of the currently allocated occurrences, the number of occurrences is not changed for the corresponding dimension.