Passing a boolean property to a command?

[Daniel Ram]

Hello Statalisters,
I am trying to write a program with an option that the user can specify as true or false. If the property is given as "option(true)", I want the command to do one thing, if it's given as "option(false)", I want it to do something else.
How could I write a Stata command that accepts a boolean property?
Here is the code for my ado file:

syntax,  red(boolean)
    if red == true{
        di in red "Hello world"
    }
    if else {
        di "Hello world"
    }

end

Here is the code I type in the console to run this program:

set trace on
helloworld, red(true)

This code returns the error "invalid syntax" for the line "syntax, red(boolean)". I have successfully passed strings, varnames and varlists with syntax to custom commands I've written in the past with similar code--can I pass a boolean like this? If so, how?
Thank you and please let me know if I can clarify this question in any way.

[Clyde Schechter]

Notwithstanding some similarities, Stata is neither Python nor C++. There is no boolean data type in Stata. Nor is there a reserved word for true or false. Boolean expressions are evaluated as numeric 0 or 1 (though any non-zero number or even a missing value will also be interpreted as true.). Once you get past that, you have some other errors in your syntax that will trip you. I have dealt also with those in the code here:

syntax, red(integer)
    if `red' {
        display in red "Hello world"
    }
    else {
        display as text "Hello world"
    }
end

[Daniel Ram]

Notwithstanding some similarities, Stata is neither Python nor C++. There is no boolean data type in Stata. Nor is there a reserved word for true or false. Boolean expressions are evaluated as numeric 0 or 1 (though any non-zero number or even a missing value will also be interpreted as true.). Once you get past that, you have some other errors in your syntax that will trip you. I have dealt also with those in the code here:

Thank you for you helpful response, Clyde.

[Leonardo Guizzetti]

-syntax- also allows for optionally on or off keywords. Here I show an equivalent approach using the optionally on approach.

cap program drop myprog
program myprog
  syntax , [myflag]
    
  if "`myflag'"!="" {
    di "-myflag- is passed - TRUE"
  }
  else {
      di "-myflag- is not passed - FALSE"
  }
end

myprog
myprog, myflag

[Daniel Ram]

-syntax- also allows for optionally on or off keywords. Here I show an equivalent approach using the optionally on approach.


[/code]

Thank you for the helpful reply Leonardo. I appreciate it!