One technique that is documented and tested and I believe should work is
the Ruby Slippers. See the docs on this, but the basic idea would be, in
the default lexer look only for commands. If the parse stops for lack of a
lexeme, give it an LHS, and resume the parse. Otherwise, or if it also
No problem, thanks for trying. I did plug it in and indeed got the same results.
On 12/2/20 6:41 PM, Jeffrey Kegler wrote:
> Oops! Ignore that last! It suffers from the same problem -- longest
> captures the match and all the rest of that hack-ish apparatus I talked about
> would be ignored
Oops! Ignore that last! It suffers from the same problem -- longest
captures the match and all the rest of that hack-ish apparatus I talked
about would be ignored.
I've been doing mainly LaTeX these days and obviously it is turning my
brain into mush.
Sorry!
On Wednesday, December 2, 2020 a
How many commands? One approach that I just thought of and have never
tested is to have fixed length variables, prioritized versus the commands
of that length.
Off the top of my head:
var2 ~ priority=>1
PA_command ~ 'PA' priority=>2
PR_command ~ 'PR' priority=>2
include a catch-all var for len
Thank you very much for your response!
1) Multiline: The language does have a "_" line-joining character, but the
grammar wouldn't have to support that - it could be done with a trivial
preprocessor. Once joined, commands may not span multiple lines.
2) Command/variable upper-case: Commands a
I'll first describe your immediate problem, then ask a couple Q's.
The problem: Lexing is LATM -- *Longest* Acceptable Token Matching. The
lexeme priority is a tie breaker, used when tokens are the same length.
When your grammar fails, "PAx" is your longest token, and the only choice
at length 3.
Hello, I'm having trouble figuring out how to express my grammar and was
hoping someone could help. I've tried rewriting various ways and looking
for some options that might change behavior, but I haven't been able to
figure it out.
I have a language with variable assignment and simple commands
