The most recent failure, or null after a successful invocation.

Checks that the script compiles with its supplied arguments without executing it. Arguments remain available for the next Run. Failure sets LastError.

Whether this script references a named external argument. Use before supplying optional host inputs. Names are case sensitive; locals do not count as external arguments.

Runs the script, returning false and setting LastError on failure.

Runs the script and reads its result. Returns default on failure or when no value is returned. An incompatible return type is reported through LastError.

Supplies a named input for the next invocation only. Unknown names and changes during execution are API usage errors. Supply every input needed to bind host member calls before running.

Creates a stack-only invocation with a temporary argument. Chain With to supply more arguments, then call Run or Compile. Names must be referenced by the script; repeated names replace earlier values.