Special-Purpose Objects for Data Storage and Retrieval

Using Special-Purpose Data Storage Objects

// decide to go back to the original
EntryUndoChanges(anEntry);

PlaySound(anEntry);

// clean up
foreach store in GetStores() do
begin
mySoup := store:GetSoup("foo:myApp:mySig") ;
if mySoup then
mySoup:RemoveFromStoreXmit(nil);
end ;
UnregUnionSoup("foo:myApp:mySig", '|foo:myApp:mySig|);

VBOs and String Data

12

In most cases, you should avoid using the

&

and

&&

string-concatenation operators

with VBO-based strings. These operators work by allocating a new string in the
NewtonScript heap and copying data from its arguments into the new object. You
can run out of heap space easily when attempting this operation with large strings.

Instead, use the

StrMunger

global function to concatenate two strings. The

following code fragment appends the

str2

string to the

str1

string, increasing

the size of

str1

as necessary, regardless of whether

str1

is VBO data or resident

in the NewtonScript heap.

StrMunger(str1, MAXINT, nil, str2, 0, nil);

The value of

MAXINT

is

1<<29-1

or

536870911

; however, any number larger

than

StrLen(str1)

works adequately.

Using Store Parts

12

This section describes how to create a store part and add soup data to it. This
discussion is followed by a description of how to access the store part's soups
from your application.

Note that other representations may provide better space efficiency or faster access
to data. Store parts are useful when you wish to avoid recoding soup data in a more
efficient representation, or when you need multiple indexes or some other
convenience that soup-based queries provide.