Allow more than one block of code to exist on a single line. Also,

Allow more than one block of code to exist on a single line. Also,
move the code which expands variables to be ran when variables are
discovered instead of in multiarg() just before execution. This means
a variable who's value is included in anothers', won't change the
others value if its own is changed.

I have also included code, which is commented out at the moment, which
implements a function map specific to interpreter. Not sure if I can
ultimately avoid using it though.