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statastata-macros

Preseting mandatory string options in syntax with default value

Consider the following toy program: 

program define table_v1.01, rclass
version 15
syntax varlist(fv min = 1 max = 1) [if] [in], pat_ID(string) = Patient_ID
end

I would like to make the option pat_ID compulsory.

In addition, since 90% of the time its value will be Patient_ID, how can I set this as a default value?

Solution

  • The following works for me:

    program define foo, rclass

syntax varlist(fv min = 1 max = 1) [if] [in], [pat_ID(string)]

if "`pat_ID'" == "" local pat_ID Patient_ID
display "`pat_ID'"

end

    Example:

    . foo i.foreign
Patient_ID

. foo i.foreign, pat_ID(Other_ID)
Other_ID

    Unlike other types of options (for example those accepting integers or reals), you cannot directly set a default value for strings. Typing help syntax will provide you with information about what is possible.