Calling Macro Variables

[hspears]

Hello,

I do not understand all the ways to correctly call Macro variables. Is there a guide of when you need to put a period after the &Macro and when you do not? I am thinking in both the context of quoted strings like a Title statement or in naming a data set in a data step. 

Thank you! 

[PaigeMiller]

A period is required to end the name of a macro variable, usually when appending text to the value of the macro variable. No period is required if there is a separator (like a space or other character that cannot be in a macro variable name).

So no period is required here

x = &macrovarname+7;

but it's also not wrong to put a period here.

A period is required here

x = &macrovarname.2;

so the 2 is appended to the value of &macrovarname.

[Tom]

You only need to period if the next character in your program could be part of the macro variable name.  Valid characters for names are letters, digits and underscore.

[Kurt_Bremser]

See Maxim 48. It's never wrong to have the dot, but sometimes very wrong to not have it.