MACRO

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MACRO macroname macroarguments

The MACRO command executes the macro (i.e., the subroutine) specified by macroname, passing it the arguments specified by macroarguments. The macro will be started in its own variable environment that is set up as a copy of the environment of the caller. This means that the subroutine gets a copy of all local variables and is free of modifying them, but that any such modification is local to the subroutine and will get lost after its execution. Hence, your subroutine will never be able to alter (or, damage) the local variables of the caller (for a different behaviour, see below, or directly refer to the STx statements MACROX, and SHELL).

The sourc file containing the macro macroname must be loaded (see the LOAD command). The macroarguments passed to the macro are stored in the variable #ARGV of the called macro. Because of the special command-line processing in STx, all string replacements are applied to and all special parsing information (e.g. quotation marks) are removed from macroarguments before it is assigned to #ARGV. For more information on argument passing, and parsing, see Argument Passing. For a broader information on macro programming, see Script Programming in STx or Becoming an S_TOOLS-STx Guru (in 240.918 simple steps).

If you want to execute a subroutine in the variable environment of the caller (which is dangerous), you will enjoy the MACROX command. If, on the other hand, you want to separate the subroutine even more thoroughly from your current environment, you may even have it executed by a separate instance of the STx shell, i.e. the STx command interpreter, by using the SHELL command for executing the subroutine.