return
return - a control flow statement that returns control from a subroutine or function
syntax
return [expression]
- expression is optional and can be numeric or string
details
return can be used in a subroutine or function to return immediately to the code that follows on the subroutine or function call. In case of a function, an optional return value can be provided. A return statement in a subroutine cannot return a value.
In normal functions the function's identifier can also be assigned a return value. But an assignment statement to a function's identifier does not immediately leave the function. If a function's return value has been assigned, any return statement thereafter without an explicit return value will return the most recently assigned value.
In an anonymous function only the return statement can be used to set a return value and leave the function.
examples
In the following example a function sets a default return value followed by a conditional return statement.
' SharpBASIC function with return, programming example
' ----------------------------------------------------
incl "lib/sys.sbi";
decl func notZero(x:int):bool;
dim n:int = 1;
dim r:bool;
main do
r = notZero(n);
print(r);
end
func notZero(n:int):bool
do
' default return value
notZero = false;
' conditional return
if n <> 0 do
return true;
end if
end
Output:
-1
In the next example a limit is passed as parameter to a subroutine to break iteration and resume control where the subroutine was called.
' SharpBASIC subroutine with return, programming example
' ------------------------------------------------------
incl "lib/sys.sbi";
decl sub printIter(lim:uint);
dim limit:uint;
main do
limit = 5;
print("limit =" + cstr(limit));
printIter(limit);
limit = 10;
print("limit =" + cstr(limit));
printIter(limit);
end
sub printIter(lim:uint)
dim i: itr;
do
for i = 1 to 9 :++ do
if i > limit do
return;
end
print(i);
end
end
Output:
limit =5
1
2
3
4
5
limit =10
1
2
3
4
5
6
7
8
9