how to past a Number to an ado Command in Stata

[qing xuan]

I have a number, for instance, the number 6, stored in a local variable, such as:

local var1 42

Now, if I have a custom command named cmdx, how should the syntax within this command be writed to accept this var1?

[Clyde Schechter]

Well, that depends on the syntax of -cmdx- itself. But the principle is this: wherever you would put 42 in the -cmdx- command, put `var1' instead.

[George Ford]

In my experience, defined locals do not pass through to programs. You have to args it.

clear all

** THIS DOES NOT WORK
program testprog
di `var1'
end

local var1 = 42
testprog

** THIS WORKS
program testprog1
args var11
di `var11'
end

local var1 = 42
testprog1 `var1'

[Jared Greathouse]

Gotta go to it and add it yourself! I use adoedit (user written, opens ado files into do files), and you'll need to pass said number as an argument

[Clyde Schechter]

Locals do not pass through into the code of programs, that is correct. But I don't think that's what O.P. is asking about. As I understand the question, there is some user-written program cmdx.ado that has some syntax. It might be:

cmdx list_of_number_arguments

OR

cmdx varlist, some_option(real n)

and wants to know how to use the contents of local macro var1 as one of the arguments, or the value of some_option. That is what my code responds to.

Of course, without knowing more about what -cmdx- is (specifically, its syntax) nobody can be sure. And O.P. provides no clues about that.

[George Ford]

By "custom command" I assumed he was writing the code.

Another option is to use a scalar, which would pass through.

[qing xuan]

George Ford's code works.
I use the following code, which works well.

program testprog2
syntax anything
di `anything'
end
local var1 = 42
testprog2 `var1'

However, I am confused about how to write the syntax when I need to receive external data such as numbers, scalar, strings, variables, matrices local/glabal, etc. What is the best way to write this syntax? Are there any good reference materials available?

[Daniel Schaefer]

See the help file for the syntax command. Typing -help syntax- into the console should pull up the help file with a link to the current documentation. There are several useful resources for programming with Stata, including this one that you may want to read.

[George Ford]

When I'm only passing a few things through to a program, I'll use args.

For more complex calls, I'll use syntax. I'd start with a basic setup program and learn from there. You'll need to learn to tokenize and so forth.

I recall Stata having a class on writing ado files that was useful.