On Friday, 19 December 2014 at 02:53:02 UTC, Rikki Cattermole
wrote:
On 19/12/2014 10:19 a.m., Kingsley wrote:
On Wednesday, 17 December 2014 at 21:05:05 UTC, Kingsley wrote:
Hi Bruno,
Thanks very much. I do have a couple of questions about DDT
in
relation to my plugin.
Firstly - I'm not too familiar with parsing/lexing but at
the moment
the Psi Structure I have implemented that comes from the DDT
parser/lexer is not in any kind of hierarchy. All the
PsiElements are
available but all at the same level. Is this how the DDT
parser
works? Or is it down to my implementation of the
Parser/Lexer that
wraps it to create some hierarchy.
For intellij it's going to be vastly easier to have a
hierarchy with
nested elements in order to get hold of a structure
representing a
class or a function for example - in order to do things like
get the
start and end lines of a class definition in order to apply
code
folding and to use for searching for classes and stuff.
Secondly - how active it the development of DDT - does it
keep up
with the D2 releases.
--Kingsley
After doing a bit more research it looks like I have to
create the psi
hierarchy myself - my current psi structure is flat because
I'm just
converting the DeeTokens into PsiElements directly. I've
still got
some experimentation to do. On the plus side I implemented
commenting,
code folding but everything else needs a psi hierarchy
I've done some more investigation and I do need to build the
parser
myself in order to create the various constructs. I've made a
start but
I haven't gotten very far yet because I don't fully understand
the
correct way to proceed.
I also had a look at using the DeeParser - because it already
does most
of what I want. However the intellij plugin wants a PsiParser
which
returns an intellij ASTNode in the primary parse method. I
can't see an
easy way to hook this up with DeeParser because the
ParsedResult
although had a node method on it - gives back the wrong type
of ASTNode.
Any pointers on how I might get the DeeParser to interface to
an
intellij ASTNode would be appreciated.
Read my codebase again, it'll answer a lot of questions. Your
parser is different, but what it produces shouldn't be. and yes
it supports hierarchies.
Hi
So finally after a lot of wrestling with the internals of
intellij I finally managed to get a working parser implementation
that produces a psi hierarchy based on the DeeParser from the ddt
code.
The main issue was that Intellij only wants you to create a
parser using their toolset - which is either with a BNF grammar
that you can then generate the parser - or with a hand written
parser. Since I'm already using the DDT lexer and there is a
perfectly good DDT parser as well - I just wanted to re-use the
DDT parser.
However Intellij does not provide any way to create a custom
AST/PSI structure or use an external parser. So I basically had
to wrap the DeeParse inside the Intellij parser and sync them up
programmatically. It's not the most efficient way in the world
but it at least works.
In the long term I will write a BNF grammar for Intellij (using
their toolkit) but I can see that will take me several months so
this is a quick way to get the plugin up and running with all the
power of intellij extras without spending several months stuck
learning all about the complexities of grammar parsing and lexing.
Thanks very much for you help. Once I get a bit more of the cool
stuff done I will release the plugin.
