A few weeks ago, in a previous post I wrote: The problem, at the time of this writing, is that neither JavaCC21 nor legacy JavaCC have any concept of characters outside of plane 0, which are the ones that require 4 bytes of internal storage. Or another way of putting this is that the assumption …
JDK 16 is out! Though JDK 16 was released on 16 March, a week ago, I only became aware of that a few days later on March 20. Once I saw that news item, I figured I would just immediately add support for the new JDK 16 language features to JavaCC. It didn’t take me …
Now that the ability to generate fault-tolerant parsers is coming along so well, I have been thinking about what to do with the Java grammar included in CongoCC. I decided that the best thing to do was to do the incremental work to make it maximally correct. Ideally, it will serve as a reference implementation …
Moving Towards a Maximally Correct Reference Java Grammar Read More »
For some time, it has been a goal of JavaCC 21 to provide the ability to generate fault-tolerant parsers. I started working on the problem about a year ago. However, I had not put in a comprehensive solution until now for several reasons. Basically these: The codebase, though already significantly refactored and cleaned up, was …
A Glimpse of the Promised Land: Fault-tolerant parsing Read More »
A Little Parlor Game As I pointed out earlier here, in this parser space, there is a great tendency to express concepts — that, once understood, are actually quite simple — in a very abstruse, obfuscated manner. Recently, I was musing about a little conceptual experiment with some real comic potential. Imagine if basic Mathematics …
It had been in the back of my mind nagging me for some time, thinking that we would eventually need some sort of preprocessor functionality moving forward, to support output for different programming languages (besides Java) and actually, even different Java targets. I had also been looking more closely at C# recently and finally, I …
(To get some prerequisite understanding of this topic, it might be a good idea to read this earlier blog post on context-sensitive tokenization from three months ago.) The Lay of the Land There are two quite useful ideas that have been in JavaCC from the very beginning: lookahead (particularly syntactic lookahead) lexical states Syntactic lookahead …
Context-Sensitive Tokenizing, Part Deux: Lexical States Read More »
Greetings, comrades! My name is Vladimir Vladimirovich Vladimirov! Hey, whassup, Vlad! As a follow-on to my blog post of a couple of days ago there were a couple of t’s that needed crossing and an ‘i’ or two that needed a dot. Let’s see… First of all, I misspoke a little bit in that post. …
Tree Building Redux: Nailing another Dmitry Dmitriyevich problem Read More »
Before getting into what the minor enhancements to tree building are, I guess I should write a quick synopsis of the current state of affairs. When you have TREE_BUILDING_ENABLED set to true (this is the default in JavaCC21) the tree building machinery will build a Node if the production results in the creation of more …
Tastes just like home-made! (Some more tree building enhancements) Read More »
I recently introduced a couple of "pseudo-annotations" (I’ll explain the pseudo part later) that can be used in code injections to express things in a much more succint manner. Here is an example: INJECT Foo : { @property String name; … } and the code generated in Foo.java corresponding to that line will be: private …