set external-function function-name to string-expression

An action that assigns the name of an external function during the running of an OmniMark program.

The values used to set the external function name can be constant string expressions, determined by program logic or derived from some input data. It's entirely up to the program.

An external function has to have a valid external function name and a valid function library name (unless it defaults) at the point of every call made to the function. These names can be changed at any time, and they take effect at the next call. This allows calls to database access functions, for example, to be rebounded to a different database system during a run.