How to declare a fixed length string

JRoark · 2022-04-05 00:24

I'm trying to figure-out how to declare a fixed length string in 5.9.9. What I'm after is something like this:

class tempType
   Var1 as ulong
   Var2 as ushort
   Var3 as string(128)
end class
dim NewType as tempType
NewType.Var3 = "This is a test"
print NewType.Var3

The goal here is to always have 128 bytes reserved for Var3. Ideally I'd also like it never to be garbage-collected... just a static array of bytes that "looks like" a regular string. Any thoughts about how to make this work?

msrobots · 2022-04-05 04:18

how about byte(128) ?

Mike

pik33 · 2022-04-13 10:39

You can alias the string as a pointer to the ubyte array, but then you cannot assign to it as every assign creates a new string with a new pointer. In the class you can write your own methods for such a "string"

dim a(128) as ubyte
dim b as ubyte pointer
declare a$ alias b as string

a(0)=65
b=@a
a(1)=0
print a$

a$="b"
print a(0)

The result:

A
65

After aliasing a$ as the pointer to a and updating a, you can print a$.
After updating a$ the pointer to a$ is no longer the pointer to a, so after assigning the new value, the pointer also changed (and was allocated, etc...)

And string(128) is an array of 128 strings (= 128 pointers)

How to declare a fixed length string

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