On Sun, Jul 20, 2014 at 10:06 AM, Ruslan Shvedov
<ruslan.shve...@gmail.com> wrote:
> Hi Paul, here are my 2cents on this, in no particular order
>
> C style #include's — aren't they supposed to be processed before parsing the
> program? The grammar has actions for include's, but I honestly can't see how
> you are going to inject the included file's contents at the recongition time
> except probably with event completed statements which will read() the
> included file contents.
An #include is "just another macro". I was thinking of doing almost
exactly as you say: spawning a second recce and using that to inject
into the main symbol table (accomplished by the "our $self = bless { }
=> __PACKAGE__ ; sub new { return $self } ; ..." trick, where $self
holds (among other things) the symbol table).
I've updated the gist https://gist.github.com/PWBENNETT/8435996 to
rename "Definition" to "Macro", and to allow an #include anywhere a
Macro is allowed, to hopefully better explain my intentions (that is,
until I actually have some "real" code to show).
> To make a long story short, if you think the language needs a preprocessor,
> write a preprocessor (or just use cpp).
Maybe. It's certainly a good idea. I don't know whether I want to have
the full capability for users to shoot themselves in the foot that cpp
might provide, but there's definitely a good case to be made for it.
> I can't see a rule for free (unbound) variables (FV (·)) and (·,·) in the
> grammar.
Syntactically I see no difference between bound and free variables
that can't be made by context.
Isn't (·,·) just the notation for what I've called a Tuple in my grammar?
> LE/le seem to include both < and <=, while the paper has only <.
The paper has, as you quote below, both < and ≤, which is incorporated
into the (revised) gist as syntactic sugar for (or sugared by?) <= (or
⩽)
> In the paper's if X then Y else Z, X seems to be a (bound) variable (not
> sure if/how they convert it to boolean, perhaps by whether it has PDF or
> not), while it is a comparison in the grammar.
The name "comparison" is just a notational thing for my convenience.
Oh, but yes. Yes, indeed. Variables are not allowed in the "X" slot in
my version. I'll have a think about that, and update the gist again
later.
Thanks for the input,
--
P/PW/PWBENNETT
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