[Python-ideas] Does jargon make learning more difficult?

[Steven D'Aprano]

On Tue, Aug 21, 2018 at 05:45:53PM -0500, Abe Dillon wrote:

> Can you explain how far the parser is capable of backtracking?

Its an LL(1) parser, if I recall correctly, so if you look at the 
details of LL(1) parsing, that should answer the question.

https://en.wikipedia.org/wiki/LL_parser

But if I'm reading the Wikipedia page correctly, I think the answer is 
"no backtracking at all".


> It seems like <expression> with <signature> would require a similar amount
> of backtracking to ternary expressions:
> 
> <expression> if <condition> else <expression>

I don't think needs any backtracking. The parser doesn't have to read 
the "if" and then go back to re-read the previous expression. It can 
look ahead from the expression by one token, see the "if", and recognise 
it is a ternary if.


-- 
Steve