Re: [Jython-users] multi-line string exec/eval

[Jim A. <ji...@tr...>]

Mark Ackerman wrote:
> 
> I've got an embedded Jython interpretor as my glue in a java program.
> I'm trying to do an exec or eval (both actually), sending an entire program
> in as a string.  It's not working.  I can use the exact same program as
> a file using execfile, and then it's fine.
> 
> Any suggestions?  I'm using \n as my line delimiter, if that helps.

It doesn't work like that: 'exec' only takes one 'unit' of code;
although you can define a function like this:

interp.exec(
           "def prt(x): \n" +
           "  print x \n" +
           "  for i in x: \n" +
           "    print i, \n" +
           "  print x.__class__\n");

(from Bruce Eckel's 'Thinking in Patterns' chap 9, the 'Interpreter
Pattern'; worth downloading from
http://www.mindview.net/Books/TIPatterns/ )

or multi-line if/for statements.

But other than that you can't run multiple lines: that is what
'execfile' is for. Note that 'execfile' DOES take an InputStream so you
can send it code from any source.

Or just put 'exec' in a loop.

Of course 'eval' takes only an EXPRESSION (and returns a result...).

-- 
                                 __o
Jim Adrig                      _ \<,_
ji...@tr...          ' `/ ' `
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