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AmigaE/NEW

 dynamic memory allocation (NEW-operator)
------------------------------------------
the NEW operator is a powerful operator for dynamic memory allocation.
it has various forms:

(assuming DEF p:PTR TO whateverobj, q:PTR TO INT)

NEW p

is an expression that will allocate zero-ised memory for the object-size
p points to. the resulting pointer will be put in p, and is also
the value of the expression. if NEW fails to get memory, it raises
a "NEW" exception. 'NEW p' is therefore roughly equivalent with:

IF (p:=New()(SIZEOF whateverobj))=NIL THEN Raise()("MEM")

with the difference that p never gets any value if an exception
is raised, and that the former is of course an expression, not
a statement

but there's more: one can also allocate an array dynamically:

NEW p[10]       /* array of 10 objects */

NEW q[a+1]      /* array of INT, size is runtime computed */

(this doesn't work when instantiating classes)
A problem with list [1,2,3] expressions sometimes is that they are static,
and when using these to build large datastructures they would need to be
created at run-time. one may then use the dynamic equivalent to static
lists:

p:=[1,2,3]:whateverobj           /* static structure */

p:=NEW [1,2,3]:whateverobj       /* dynamicly allocated! */

this works with both lists and typed-lists, and also with arrays:

NEW [1,2,3]        /* constant-list, dyn. (note: not a like a listvar!) */
NEW [1,2,3]:obj    /* object */
NEW [1,2,3]:INT    /* array of INTs */

freeing memory allocated with any variations of NEW is done automatically
at the end of the program, or by hand with END or FastDispose()().
(note: the only exception is NEW , use FastDisposeList()())

If you use NEW [...]:obj, and the number of fields is less than the
one present in the object, additional 0/NIL/"\0" whatever fields will
be added. this allows one to extend objects without getting into
trouble with allocations like these. (note that this is different
from the static [...]:obj)

when you use NEW as a statement, multiple pointers may follow, i.e.:

	NEW a,b.create(),c

is valid.

See END,
    New()(),Dispose()(),
    NewR()(), NewM()(), FastNew()(), FastDispose()(), FastDisposeList()(),
    DisposeLink()()



Logo by Emeric/SH
AmigaE/NEW

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Functions with "N":
NEW
NEWFILE
NIL
New()
NewM()
NewR()
Next()
Not()

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