Re: [F-Script-talk] Multiple Blocks

[Ken F. <ken...@gm...>]

On 9/7/06, Jeremy Sacket <js...@ga...> wrote:
>
> I am trying to implement extensions into my app.  I am wanting to define
> blocks in one file and then run only blocks that I call.
> Example:
>
> [
>  name:=[ sys log:('Jeremy').]
>  description:=[ :des| sys log:('des).]
> ]
>
> Now I want to just execute the "name" block.

Executing the big outer block will dump a definition for 'name' and
'description' in the enviroment that executes the block.  Executing
the outer block will not execute the inner blocks.  So, you could do
this:

(typed in gmail, and skipping all the error handling for conciseness.
Note that the example string above won't compile as a block.)

> -(id)runProcedure
> {
>  // will set fscript to the above example.
>  NSString *fscript = [procedure objectForKey:@"procedure"];

  FSInterpreter *interpreter = [FSInterpreter interpreter];
  System *sys = [interpreter objectForIdentifier:@"sys" found:NULL];
  Block *outerBlock = [sys blockFromString:fscript]; // block is
compiled in the environment of the interpreter
  [outerBlock value]; //.. so the 'name' identifier is bound in the interpreter
  Block *nameBlock = [interpreter objectForIdentifier:@"name" found:NULL];
  [nameBlock value];
}

It might seem a little less indirect if the file contained statements
without the big enclosing block.  Then you could use -[FSInterpreter
execute:] to execute the string, and -[FSInterpreter
objectForIdentifier:found:] to retrieve the blocks bound in the
interpreter as a result.

-Ken