Hi,
I am relatively new to DS2 and have a question about the scope of global variable assignments. See the following program.
proc ds2;
data _null_;
declare int x; /* global x in global scope */
declare int y; /* global y in global scope */
/* retain x y; */
method init();
declare int x; /* local x in local scope */
x = 5; /* local x assigned 5 */
y = 6; /* global y assigned 6 */
put '0. in init() ' x= y=;
end;
method run();
put '1. in run() ' x= y=;
x = 1;
put '2. in run() ' x= y=;
end;
method term();
put '3. in term() ' x= y=;
end;
enddata;
run;
quit;
Here is the log:
0. in init() x=5 y=6
1. in run() x= y=6
2. in run() x=1 y=6
3. in term() x= y=Both x and y are global variables. Variable y is assigned a value of 6 in the init() method and this value is still present in the run() method, as I would expect. However, y no longer has the assigned value in the term() method. Why is this?
By the way, explicitly retaining y seems to solve the problem, but I don't understand why this is necessary. Can anyone explain?
The TERM() method automatically resets global variables to uninitialized values.
There are a few situations where this will not occur, pre-defined variables, such as _N_, accumulator variables used in sum statements, variables specified in a RETAIN statement and package variables will not automatically be reset to uninitialized values in the TERM() method.
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