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Topic: questions concerning procedural types (Read 586 times)
anonymousstranger
New Member
Posts: 49
questions concerning procedural types
«
on:
January 17, 2021, 02:54:42 am »
1) Given:
Code: Pascal
[Select]
[+]
[-]
Type
TOneArgCcall
=
Procedure
(
Var
X
:
integer
)
;
var
proc
:
TOneArgCcall
;
Procedure
printit
(
Var
X
:
Integer
)
;
begin
WriteLn
(
x
)
;
end
;
begin
Proc
:
=
@
printit
;
end
.
How does one pass a value into printit through proc? I'm kind of fuzzy on how this works.
2)Say you have a procedural type that references a procedure/function in a library. does the procedural type also require the "external" tag?
«
Last Edit: January 17, 2021, 03:05:41 am by anonymousstranger
»
Logged
Blaazen
Hero Member
Posts: 3237
POKE 54296,15
Re: questions concerning procedural types
«
Reply #1 on:
January 17, 2021, 03:22:35 am »
Since you pass variable x by reference (
var
), you have to write:
Code: Pascal
[Select]
[+]
[-]
var
i
:
Integer
;
begin
Proc
:
=
@
printit
;
i
:
=
5
;
Proc
(
i
)
;
end
;
i
can be global variable as well.
Don't know about external keyword.
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anonymousstranger
New Member
Posts: 49
Re: questions concerning procedural types
«
Reply #2 on:
January 17, 2021, 05:09:13 am »
cool
thanks.
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