<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> </head> <body text="#000000" bgcolor="#FFFFFF"> <tt>Concerning question 3, at least in TDL and PET there was no such restriction,<br> but that could make the definition of docstrings easier.<br> <br> Best,<br> <br> Bernd<br> </tt><br> <div class="moz-cite-prefix">On 11.07.2018 03:01, Michael Wayne Goodman wrote:<br> </div> <blockquote type="cite" cite="mid:CAP=XfC2q0Koi4PTN9Fg-ECXyt6HpDnAXbtOG5jXDH_k59O1WfQ@mail.gmail.com"> <div dir="ltr"> <div>I attempted to define a BNF-like description of TDL syntax on the wiki: <a href="http://moin.delph-in.net/TdlRfc" moz-do-not-send="true">http://moin.delph-in.net/TdlRfc</a></div> <div>I tried to follow the partial BNF in the LKB source and often referred to the lisp code itself in order to fill out the rest of the description.<br> </div> <div><br> </div> <div>My 3 questions above are concisely repeated at the bottom of the wiki along with some others.</div> <div><br> </div> <div>I welcome corrections and discussion (here or on the wiki) from any TDL nerds or authorities (especially if you've written a TDL parser).<br> </div> </div> <div class="gmail_extra"><br> <div class="gmail_quote">On Mon, Jul 9, 2018 at 12:49 PM, Michael Wayne Goodman <span dir="ltr"><<a href="mailto:goodmami@uw.edu" target="_blank" moz-do-not-send="true">goodmami@uw.edu</a>></span> wrote:<br> <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <div dir="ltr"> <div>Hi developers,</div> <div><br> </div> <div>I'm taking a closer look at the syntax of TDL files and the situation is a bit of a mess. Can anyone help me clarify some things? (I'll restrict myself to 3 questions for now)<br> </div> <div><br> </div> <div>The Copestake 2002 reference (Implementing TFS Grammars) has a BNF for TDL, but it's a bit out of date and, according to comments in the LKB source code, incorrect in parts. The LKB source comments are scattered, incomplete, inconsistent, and also a bit outdated. There is not much on the wiki. There is some discussion in the mailing list archives (much from before my time in DELPH-IN), but it's not clear how current those descriptions are.</div> <div><br> </div> <div>Q1: Are supertypes special in a definition?</div> <div><br> </div> <div>The BNF (in the LKB source) says this:</div> <div><br> </div> <div> Type-def -> Type { Avm-def | Subtype-def} . | <br> Type { Avm-def | Subtype-def}.<br> </div> <div> Avm-def -> := Conjunction | Comment Conjunction<br> Conjunction -> Term { & Term } *<br> Term -> Type | Feature-term | Diff-list | List | Coreference<br> </div> <div><br> </div> <div>That makes it sound like I could do this:</div> <div><br> </div> <div> mytype := [ FEAT val ] & supertype.</div> <div><br> </div> <div>or even:</div> <div><br> </div> <div> mytype := <! diff list.. !> & #coref & supertype.</div> <div><br> </div> <div>But elsewhere it seems like a list of parents is special and appears before the rest of the conjunction. E.g., at read-tdl-avm-def of lingo/lkb/src/io-tdl/<wbr>tdltypeinput.lsp I see this alternate definition of Avm-def:<br> </div> <div><br> </div> <div> ;;; Avm-def -> := Parents Conjunction | Parents Comment Conjunction |<br> ;;; Parents | Parents Comment<br> </div> <div><br> </div> <div>It seems that both ACE and PET are fine with putting supertypes after the feature list (and some other variations). I'm fine with this, but I wonder what it means for docstrings (see Q3 below), which (I think) are supposed to appear after the list of parents and before the feature list.<br> </div> <div><br> </div> <div><br> </div> <div>Q2: Subtype-def is now just a variant of Avm-def, yes?</div> <div><br> </div> <div>The BNF still describes subtyping (with the :< operator) as only taking a single parent:</div> <div><br> </div> <div> Subtype-def -> :< type</div> <div><br> </div> <div>But I believe the consensus is that this is unnecessary (it's equivalent to using := with only a supertype), so :< is treated as equivalent to := (to avoid breaking backward compatibility). Is this interpretation used by all processors?</div> <div><br> </div> <div><br> </div> <div>Q3: What's the final word with type comments / docstrings?</div> <div><br> </div> <div>I find evidence of 3 proposed variants: (1) a block of ";" comments before a typename (LTDB-style); (2) a block of ";" comments within a type description; and (3) a "doc string" within a type description. Furthermore, there is a question as to whether comments or strings within a type go after the ":=" or after the list of supertypes. I think #| ... |# comments were not considered for this purpose.</div> <div><br> </div> <div>My guess is this:</div> <div><br> </div> <div>* LTDB-style comments (before the type identifier) are processed separately from TDL-parsing</div> <div>* type-internal comments can go anywhere but are discarded</div> <div>* type-internal doc strings must appear after the list of supertypes and are later available for inspection (they are included as a non-functional part of a type)</div> <div><br> </div> <div>ACE seems happy with my assumptions, although PET doesn't seem to like doc strings at all.<br> </div> <div><br> </div> <div><br> </div> <div>Thanks!<span class="HOEnZb"><font color="#888888"><br> </font></span></div> <span class="HOEnZb"><font color="#888888"> <div><br> </div> <div>-- <br> <div class="m_-3591690003182791182gmail_signature"> <div dir="ltr"> <div> <div dir="ltr"> <div> <div dir="ltr">Michael Wayne Goodman</div> </div> </div> </div> </div> </div> </div> </font></span></div> </blockquote> </div> <br> <br clear="all"> <br> -- <br> <div class="gmail_signature" data-smartmail="gmail_signature"> <div dir="ltr"> <div> <div dir="ltr"> <div> <div dir="ltr">Michael Wayne Goodman</div> </div> </div> </div> </div> </div> </div> </blockquote> <br> <pre class="moz-signature" cols="72">-- ---------------------------------------------------------------------- Bernd Kiefer DFKI GmbH, Stuhlsatzenhausweg, D-66123 Saarbruecken <a class="moz-txt-link-abbreviated" href="mailto:kiefer@dfki.de">kiefer@dfki.de</a> +49-681/85775-5301 (phone) +49-681/85775-5338 (fax) ---------------------------------------------------------------------- Deutsches Forschungszentrum fuer Kuenstliche Intelligenz GmbH Trippstadter Strasse 122, D-67663 Kaiserslautern, Germany Geschaeftsfuehrung: Prof. Dr. Dr. h.c. mult. 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