11.10 Commands

Commands are a special class of functions that only accept string input arguments. A command can be called as an ordinary function, but it can also be called without the parentheses like the following example shows

     my_command hello world

which is the same as

     my_command("hello", "world")

The general form of a command call is

     name arg1 arg2 ...

which translates directly to

     name ("arg1", "arg2", ...)

A function can be used as a command if it accepts string input arguments. To do this, the function must be marked as a command, which can be done with the mark_as_command command like this

     mark_as_command name

where name is the function to be marked as a command.

One difficulty of commands occurs when one of the string input arguments are stored in a variable. Since Octave can't tell the difference between a variable name, and an ordinary string, it is not possible to pass a variable as input to a command. In such a situation a command must be called as a function.