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From: gah4@u.washington.edu
Newsgroups: comp.compilers
Subject: Re: Spell checking identifiers
Date: Tue, 23 Jun 2020 16:51:38 -0700 (PDT)
Organization: Compilers Central
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On Tuesday, June 23, 2020 at 12:59:35 PM UTC-7, Johann 'Myrkraverk' Oskarsson wrote:

(snip)

> This clang blog specifically mentions Levenshtein,

> http://blog.llvm.org/2010/04/amazing-feats-of-clang-error-recovery.html#spell_checker

> and it looks like what people do is to go through the entire symbol
> table and compute it against the individual erroneous identifier.

> I thought that'd be a bit on the expensive side,

With either constant weighting or character dependent weighting
it is easy to do with dynamic programming. The time is then O(m n)
where m and n are the two lengths.

It seems most obvious to do only variable that are in the appropriate
scope to be misspelled, but I suspect catching variables used out
of scope is also worth doing.  Well, in the latter case, you could
hope that they at least spell them the same.

I think you should turn it off for one character names, though,
even though I suspect those are more likely. Too many false
positives!