Lag variables by group and set all lags to missing

[catkat96]

I have this code (don't consider a data snippet necessary in this case, let me know).

data temp;
set test;
by id;
lag_1=lag(var1);
lag_2=lag(var2);
lag_3=lag(var3);
lag_4=lag(var4);
lag_5=lag(var5);
if first.id then lag_:=.;
run;

I tried this and on the last line it gives me an error: "statement is not valid or it is used out of proper order". 

I also tried to do 

if first.id then lag_1-lag_5=.;

but it gives me the same error. 

I'm sure this is very stupid, but how can I do it so that I don't have to write all 5 (in reality I have around 60 lagged variables I need to do, hence why I need the short way)?

[Tom · Accepted solution]

You can use CALL MISSING() to set multiple variables to missing on one function call.

if first.id then call missing(of lag_:);

[ballardw]

CALL MISSING will set a list of variables to missing values.

Call missing is also one of the few functions that will take both numeric and character variables in a single function call.

if first.id then call missing (lag_1 - lag_5);

In general you only get one variable as the target of an = sign.