[andythenorth]

#439 increased pre-processing time from ~4s to ~16s with Iron Horse nml.

The checking of similar names loops all of item names with a comparator. This will be some O(n) complexity that I am not skilled enough to figure out.

This patch puts a crude cache in of already seen names, using dict key lookup, which is usually fast.

With the patch applied, Iron Horse compile is ~4s.

However adding a cache usually means there are now 2 problems. I am unclear if anything else would need to fill or read this cache.

[LordAro]

I'm not sure I follow - item_names is already a dict, why can't that be used, rather than adding a new container?

if self.name.value in global_constants.item_names:
   ...
else:
    casefolded = self.name.value.casefold()
    if casefolded in global_constants.item_names:
        ...
    else:
        ...

(could use := to allow an elif chain)

No idea what I'm doing

[PeterN]

Although item_names is already a dict, the names within it are not casefolded, so I guess a second dict of casefolded names is required